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The purpose of this paper is to investigate the effect of a hydrostatic initial stress and the gravity field on a fiber-reinforced thermoelastic medium with an internal heat source that is moving with a constant speed.

A general model of the equations of the formulation in the context of the three-phase-lag model and Green-Naghdi theory without energy dissipation.

The exact expressions for the displacement components, force stresses, and the thermal temperature for the thermal shock problem obtained by using normal mode analysis.

A comparison made between the results of the two models for different values of a hydrostatic initial stress as well as an internal heat source. Comparisons also made with the results of the two models in the absence and presence of the gravity field as well as the reinforcement.

In the present article, the three-phase-lag (3PHL) model and the Green-Naghdi theory of types II, III with memory-dependent derivative is used to study the effect of rotation on a nonlocal porous thermoelastic medium.

In this study normal mode analysis is used to obtain analytical expressions of the physical quantities. The numerical results are given and presented graphically when mechanical force is applied.

The model is illustrated in the context of the Green-Naghdi theory of types II, III and the three-phase lags model. Expressions for the physical quantities are solved by using the normal mode analysis and represented graphically.

Comparisons are made with the results predicted in the absence and presence of the rotation as well as a nonlocal parameter. Also, the comparisons are made with the results of the 3PHL model for different values of time delay.

The present study discussed wave propagation in a nonlocal generalized thermoelastic half-space with moving an internal heat source under influence of rotation.

Normal mode analysis is introduced to obtain the analytical expressions of the physical quantities.

Numerical results are presented graphically to explore the effects of rotation, the nonlocal parameter, and the time-delay on the physical quantities. It is found that the physical quantities are affected by rotation, the nonlocal parameter, and the time-delay.

The problem is solved based on the classical-coupled theory, the Lord–Shulman theory, and the Green–Lindsay theory with memory-dependent derivative (MDD).

The purpose of this paper is to investigate the effect of rotation and a magnetic field on the wave propagation in a generalized thermoelastic problem for a medium with an internal heat source that is moving with a constant speed.

The formulation is applied to a generalized thermoelastic problem based on the three-phase-lag model and Green-Naghdi theory without energy dissipation. The medium is a homogeneous isotropic thermoelastic in the half-space.

The exact expressions of the displacement components, temperature, and stress components are obtained by using normal mode analysis.

Comparisons are made with the results predicted by the two models in the absence and presence of a magnetic field as well as a rotation. A comparison also is made with the results predicted by the two models for two different values of an internal heat source.

The purpose of this paper is to investigate the influences of fractional order, hydrostatic initial stress and gravity field on the plane waves in a linearly fiber-reinforced isotropic thermoelastic medium.

The problem has been solved analytically and numerically by using the normal mode analysis.

Numerical results for the temperature, the displacement components and the stress components are presented graphically and analyzed the results. The graphical results indicate that the effect of fractional order, hydrostatic initial stress and gravity field on the plane waves in the fiber-reinforced thermoelastic medium are very pronounced. Comparisons are made with the results in the absence and presence of hydrostatic initial stress and gravity field.

In the present work, the authors shall formulate a fiber-reinforced two-dimensional problem under the effect of fractional order, hydrostatic initial stress, and gravity field. The normal mode analysis is used to obtain the exact expression for the temperature, displacement components, and stress components. A comparison is also made between the three theories in the absence and presence of gravity field. Such problems are very important in many dynamical systems.

The dual-phase-lag (DPL) model and Lord-Shulman theory with one relaxation time are applied to study the effect of the gravity field, the magnetic field, and the hydrostatic initial stress on the wave propagation in a two-temperature generalized thermoelastic problem for a medium with an internal heat source that is moving with a constant speed. The paper aims to discuss this issue.

The exact expressions of the considered variables are obtained by using normal mode analysis.

Numerical results for the field quantities are given in the physical domain and illustrated graphically in the absence and presence of the gravity field as well as the magnetic field. Comparisons are made between the results of the two different models with and without temperature dependent properties and for two different values of the hydrostatic initial stress. A comparison is also made between the results of the two different models for two different values of the time.

In the present work, the author shall formulate a two-temperature generalized magneto-thermoelastic problem for a medium with temperature dependent properties and with an internal heat source that is moving with a constant speed under the influence of a gravity field and a hydrostatic initial stress. Normal mode analysis is used to obtain the exact expressions for the displacement components, thermodynamic temperature, conductive temperature, and stress components. A comparison is carried out between the considered variables as calculated from the generalized thermoelasticity based on the DPL model and the L-S theory in the absence and presence of a magnetic field as well as a gravity field. Comparisons are also made between the results of the two theories with and without temperature dependent properties and for two different values of hydrostatic initial stress. A comparison is also made between the results of the two different models for two different values of the time.

In the present paper, the three-phase-lag (3PHL) model, Green-Naghdi theory without energy dissipation (G-N II) and Green-Naghdi theory with energy dissipation (G-N III) are used to study the influence of the gravity field on a two-temperature fiber-reinforced thermoelastic medium.

The analytical expressions for the displacement components, the force stresses, the thermodynamic temperature and the conductive temperature are obtained in the physical domain by using normal mode analysis.

The variations of the considered variables with the horizontal distance are illustrated graphically. Some comparisons of the thermo-physical quantities are shown in the figures to study the effect of the gravity, the two-temperature parameter and the reinforcement. Also, the effect of time on the physical fields is observed.

To the best of the author’s knowledge, this model is a novel model of plane waves of two-temperature fiber-reinforced thermoelastic medium, and gravity plays an important role in the wave propagation of the field quantities. It explains that there are significant differences in the field quantities under the G-N II theory, the G-N III theory and the 3PHL model because of the phase-lag of temperature gradient and the phase-lag of heat flux.

The recognition of children and young people as active agents, not merely passive subjects, has become a cornerstone of much research undertaken in the social sciences over the last three decades. Reflecting on research with young carers, this paper describes the research techniques employed to actively engage these children and young people in order to gain insight into their experiences of providing care. It concludes with a discussion of the benefits and disadvantages of the research methods, and the issues of ethics and consent.

The purpose of this paper is to understand the tensions that marketing practitioners in social enterprises experience, and to explore how these tensions impact the development and implementation of marketing activities.

Using an approach informed by grounded theory, this paper reports on an investigation of the tensions facing 15 social enterprises. The primary data comprises semi-structured interviews with senior marketing decision-makers, supplemented with archival sources.

The analysis shows tensions and dualities inform the social and commercial strategic marketing activities of the social enterprises. These tensions and dualities are linked to how the organization obtains financial resources, the nature of the organization’s growth, working with myriad stakeholders and competitive versus cooperative pressures. A model outlining the dualities and their links to marketing activities is developed.

The study provides an in-depth analysis of a small, regional sample of Canadian social enterprises. The study serves as a foundation for future research aimed at elaborating the model we propose.

The findings point to tensions and dualities that play an important role in enabling and restricting the development and implementation of strategic marketing activities in social enterprises. Understanding the nature of these dualities is crucial for social enterprise managers and social marketers as they develop strategic activities.

Social enterprises engage in activities that offer substantial social benefits, yet the development of marketing activities in these organizations requires confronting tensions that must be carefully managed.

This paper highlights how dualities facing marketing practitioners in social enterprises influence the development of both social and for-profit marketing activities. The paper offers a model of these dualities. The findings help to extend our understanding of the complex environmental influences impacting marketing practices within social enterprise organizations. Understanding the nature of these environmental influences helps to attune marketers to the potential opportunities and challenges of using social enterprise as an organizational form for launching social marketing programs, as well as providing a theoretical basis for future investigations of marketing practice in social enterprise and social marketing organizations.

In this chapter, we examine the role of charismatic leadership in postcolonial Tanzania. Primarily used in sociological and political analysis, the concept of charisma has been viewed as a central component in nation-building in postcolonial Africa. Based on a decolonial perspective, we discuss charismatic leadership in Tanzania, focusing on Julius Nyerere, the first president of Tanzania. Nyerere, one of Africa's most influential leaders of the mid-twentieth century, fought the colonial rule, pushed for national independence and political freedom, and offered radical solutions to colonialism. Finally, the future directions regarding leadership in postcolonial Tanzania are discussed.