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The purpose of this paper is to present a new method based on the homotopy analysis method (HAM) with the aim of fast searching and calculating multiple solutions of nonlinear boundary value problems (NBVPs).

A major problem with the previously modified HAM, namely, predictor homotopy analysis method, which is used to predict multiplicity of solutions of NBVPs, is a time-consuming computation of high-order HAM-approximate solutions due to a symbolic variable namely “prescribed parameter”. The proposed new technique which is based on traditional shooting method, and the HAM cuts the dependency on the prescribed parameter.

To demonstrate the computational efficiency, the mentioned method is implemented on three important nonlinear exactly solvable differential equations, namely, the nonlinear MHD Jeffery–Hamel flow problem, the nonlinear boundary value problem arising in heat transfer and the strongly nonlinear Bratu problem.

The more high-order approximate solutions are computable, multiple solutions are easily searched and discovered and the more accurate solutions can be obtained depending on how nonhomogeneous boundary conditions are transcribed to the homogeneous boundary conditions.

This paper aims to numerically investigate the two-dimensional unsteady laminar magnetohydrodynamic bioconvection flow and heat transfer of an electrically conducting non-Newtonian Casson thin film with uniform thickness over a horizontal elastic sheet emerging from a slit in the presence of viscous dissipation. The composite effects of variable heat, mass, nanoparticle volume fraction and gyrotactic micro-organism flux are considered as is hydrodynamic (wall) slip. The Buongiorno nanoscale model is deployed which features Brownian motion and thermophoresis effects. The model studies the manufacturing fluid dynamics of smart magnetic bio-nano-polymer coatings.

The coupled non-linear partial differential boundary-layer equations governing the flow, heat and nano-particle and micro-organism mass transfer are reduced to a set of coupled non-dimensional equations using the appropriate transformations and then solved as an nonlinear boundary value problem with the semi-numerical Liao homotopy analysis method (HAM).Validation with a generalized differential quadrature (GDQ) numerical technique is included.

An increase in velocity slip results in a significant decrement in skin friction coefficient and Sherwood number, whereas it generates a substantial enhancement in Nusselt number and motile micro-organism number density. The computations reveal that the bioconvection Schmidt number decreases the micro-organism concentration and boundary-layer thickness which is attributable to a rise in viscous diffusion rate. Increasing bioconvection Péclet number substantially elevates the temperatures in the regime, thermal boundary layer thickness, nanoparticle concentration values and nano-particle species boundary layer thickness. The computations demonstrate the excellent versatility of HAM and GDQ in solving nonlinear multi-physical nano-bioconvection flows in thermal sciences and furthermore are relevant to application in the synthesis of smart biopolymers, microbial fuel cell coatings, etc.

The numerical study is valid for two-dimensional, unsteady, laminar Casson film flow with nanoparticles over an elastic sheet in presence of variable heat, mass and nanoparticle volume fraction flux. The film has uniform thickness and flow is transpiring from slit which is fixed at origin.

The study has significant applications in the manufacturing dynamics of nano-bio-polymers and the magnetic field control of materials processing systems. Furthermore, it is relevant to application in the synthesis of smart biopolymers, microbial fuel cell coatings, etc.

The originality of the study is to address the simultaneous effects of unsteady and variable surface fluxes on Casson nanofluid transport of gyrotactic bio-convection thin film over a stretching sheet in the presence of a transverse magnetic field. Validation of HAM with a GDQ numerical technique is included. The present numerical approaches (HAM and GDQ) offer excellent promise in simulating such multi-physical problems of interest in thermal thin film rheological fluid dynamics.

The purpose of this paper is to explore the novel aspects of activation energy in the nonlinearly convective flow of Walter-B nanofluid in view of Cattaneo–Christov double-diffusion model over a permeable stretched sheet. Features of nonlinear thermal radiation, dual stratification, non-uniform heat generation/absorption, MHD and binary chemical reaction are also evaluated for present flow problem. Walter-B nanomaterial model is employed to describe the significant slip mechanism of Brownian and thermophoresis diffusions. Generalized Fourier’s and Fick’s laws are examined through Cattaneo–Christov double-diffusion model. Modified Arrhenius formula for activation energy is also implemented.

Several techniques are employed for solving nonlinear differential equations. The authors have used a homotopy technique (HAM) for our nonlinear problem to get convergent solutions. The homotopy analysis method (HAM) is a semi-analytical technique to solve nonlinear coupled ordinary/partial differential equations. The capability of the HAM to naturally display convergence of the series solution is unusual in analytical and semi-analytic approaches to nonlinear partial differential equations. This analytical method has the following great advantages over other techniques:

• It provides a series solution without depending upon small/large physical parameters and applicable for not only weakly but also strongly nonlinear problems.

• It guarantees the convergence of series solutions for nonlinear problems.

• It provides us a great choice to select the base function of the required solution and the corresponding auxiliary linear operator of the homotopy.

It provides a series solution without depending upon small/large physical parameters and applicable for not only weakly but also strongly nonlinear problems.

It guarantees the convergence of series solutions for nonlinear problems.

It provides us a great choice to select the base function of the required solution and the corresponding auxiliary linear operator of the homotopy.

Brief mathematical description of HAM technique (Liao, 2012; Mabood et al., 2016) is as follows. For a general nonlinear equation:

where N denotes a nonlinear operator, x the independent variables and u(x) is an unknown function, respectively. By means of generalizing the traditional homotopy method, Liao (1992) creates the so-called zero-order deformation equation:

here q∈[0, 1] is the embedding parameter, H(x) ≠ 0 is an auxiliary function, h(≠ 0) is a nonzero parameter, L is an auxiliary linear operator, u_o(x) is an initial guess of u(x) and u ˆ ( x ; q ) is an unknown function, respectively. It is significant that one has great freedom to choose auxiliary things in HAM. Noticeably, when q=0 and q=1, following holds:

Expanding u ˆ ( x ; q ) in Taylor series with respect to (q), we have:

If the initial guess, the auxiliary linear operator, the auxiliary h and the auxiliary function are selected properly, then the series (4) converges at q=1, then we have:

By defining a vector u → = ( u o ( x ) , u 1 ( x ) , u 2 ( x ) , … , u n ( x ) ) , and differentiating Equation (2) m-times with respect to (q) and then setting q=0, we obtain the mth-order deformation equation:

where:

Applying L⁻¹ on both sides of Equation (6), we get:

In this way, we obtain u_m for m ⩾ 1, at mth-order, we have:

It is evident from obtained results that the nanoparticle concentration field is directly proportional to the chemical reaction with activation energy. Additionally, both temperature and concentration distributions are declining functions of thermal and solutal stratification parameters (P₁) and (P₂), respectively. Moreover, temperature Θ(Ω₁) enhances for greater values of Brownian motion parameter (N_b), non-uniform heat source/sink parameter (B₁) and thermophoresis factor (N_t). Reverse behavior of concentration ϒ(Ω₁) field is remarked in view of (N_b) and (N_t). Graphs and tables are also constructed to analyze the effect of different flow parameters on skin friction coefficient, local Nusselt number, Sherwood numbers, velocity, temperature and concentration fields.

The novelty of the present problem is to inspect the Arrhenius activation energy phenomena for viscoelastic Walter-B nanofluid model with additional features of nonlinear thermal radiation, non-uniform heat generation/absorption, nonlinear mixed convection, thermal and solutal stratification. The novel aspect of binary chemical reaction is analyzed to characterize the impact of activation energy in the presence of Cattaneo–Christov double-diffusion model. The mathematical model of Buongiorno is employed to incorporate Brownian motion and thermophoresis effects due to nanoparticles.

Barriers to employment are a significant issue in the United States and abroad. As civil rights legislation continues to be enforced and as employers seek to diversify their workplaces, it is incumbent upon the management field to offer insights that address obstacles to work. Although barriers to employment have been addressed in various fields such as psychology and economics, management scholars have addressed this issue in a piecemeal fashion. As such, our review will offer a comprehensive, integrative model of barriers to employment that addresses both individual and organizational perspectives. We will also address societal-level concerns involving these barriers. An integrative perspective is necessary for research to progress in this area because many individuals with barriers to employment face multiple challenges that prevent them from obtaining and maintaining full employment. While the additive, or possibly multiplicative, effect of employment barriers have been acknowledged in related fields like rehabilitation counseling and vocational psychology, the Human Resource Management (HRM) literature has virtually ignored this issue. We discuss suggestions for the reduction or elimination of barriers to employment. We also provide an integrative model of employment barriers that addresses the mutable (amenable to change) nature of some barriers, while acknowledging the less mutable nature of others.

Based on the social exchange theory, this study explores the mechanism of leader–subordinate power distance orientation (PDO) congruence with employees' taking charge behavior (TCB) and also verifies the moderated mediation effect of employees' promotion regulatory focus (PROM-F) on leader–subordinate PDO congruence and on employees' TCB through trust in the leader (which is the mediator).

Based on 296 questionnaires from 46 teams of Chinese enterprises, the authors use cross-level polynomial regressions and response surface techniques to analyze the effect of leader–subordinate PDO congruence on employees' TCB and use the block variable technique to test the mediating effect of trust in the leader.

(1) When leader–subordinates' PDO is congruent, the leader–subordinate low-low PDO matching pattern leads to more employees' TCB than the leader–subordinate high-high PDO matching pattern. (2) When leader–subordinate PDO is incongruent, the leader–subordinate low–high PDO matching pattern will lead to more TCB than the high-low PDO pattern.

(1) Encourage and promote the development of diverse cultures in enterprises. (2) Respect the power and status of employees and encourage a low-PDO leadership style. (3) Increase credibility by developing and establishing a good corporate leader image.

(1) The unique background of this survey offers important cross-cultural information on the effects of leader–subordinate PDO congruence. (2) The results of this research enrich the theoretical understanding of the factors that influence TCB. (3) Reveal the internal mechanisms of CPD congruence with TCB and demonstrate an indirect effect of trust in leader. (4) The discussion of the moderating role of employee's PROM-F will also deepen the understanding of the exchange relationship between leaders and subordinates.

Meetings are an integral function in organizations where interaction between leaders and their employees and thus, leadership, happens. A small but growing area of research within the larger workplace meetings domain has started to focus on the role of leaders in promoting effective and satisfying meetings. This chapter provides an overview of research to date on workplace meetings and leadership, and the authors identified seven studies that paired the two areas. The number of publications focusing on meetings and leadership is increasing, with the older papers largely dedicated to qualitative investigations of leader behaviors associated with successful meetings, whereas the more recent papers take a more theoretical and quantitative approach, yet are nonetheless largely isolated from one another. Next, the authors review five theories of leadership (full range of leadership, charismatic leadership, servant leadership, exploitative leadership, and followership), and relate each of the theories to workplace meetings, with a key focus on how the theory may impact subordinates’ perceptions of meetings as well as the utility of meetings for team and organizational functioning. The authors propose seven areas throughout the chapter that future research could explore to extend knowledge about how leadership operates in meetings and how meetings are an important aspect to consider with respect to leadership theories. Primary theoretical contributions are the integration of existing work on leadership and meetings and theoretically based propositions for future research.

Effective internal control over financial reporting (ICFR) should either prevent or enable correction of any material misstatement in a firm’s financial statements. Independent auditors, guided by professional standards, prepare an ICFR audit report, which provides a gauge by which the public can evaluate the reliability of a firm’s financial information. A firm manager may be tempted to misstate financial statements if he/she perceives a substantial reward for doing so. This study examines whether managers and firms are rewarded for misstating their financial statements in situations where there are incentives to do so, specifically, when an industry-leading peer is fraudulently inflating its reported earnings. The authors test to see if managers experience an increase in compensation as a result of misstatement. The authors also test to see if their firms benefit from misstating via changes to their cost of capital. Results suggest that neither managers nor their firms benefit from managing earnings by misstating financial statements. These findings are important, because a manager who ex ante understands that misstating will not lead to benefits personally or his/her firm is less likely to misstate in the first place.

The purpose of this paper is to focus on the application of Chebyshev spectral collocation methodology with Gauss Lobatto grid points to micropolar fluid over a stretching or shrinking surface. Radiation, thermophoresis and nanoparticle Brownian motion are considered. The results have attainable scientific and technological applications in systems involving stretchable materials.

The model equations governing the flow are transformed into non-linear ordinary differential equations which are then reworked into linear form using the Newton-based quasilinearization method (SQLM). Spectral collocation is then used to solve the resulting linearised system of equations.

The validity of the model is established using error analysis. The velocity, temperature, micro-rotation, skin friction and couple stress parameters are conferred diagrammatically and analysed in detail.

The study obtains numerical explanations for rapidly convergent solutions using the spectral quasilinearization method. Convergence of the numerical solutions was monitored using the residual error analysis. The influence of radiation, heat and mass parameters on the flow are depicted graphically and analysed. The study is an extension on the work by Zheng et al. (2012) and therefore the novelty is that the authors tend to take into account nanoparticles, Brownian motion and thermophoresis in the flow of a micropolar fluid.

This chapter provides a multilevel perspective on the impact of leaders’ emotional display and control on subordinates’ job satisfaction.

This multilevel study investigates how the association of employees’ perceived immediate leaders’ servant leadership and their job satisfaction is influenced by leaders’ emotional labor. Participants in this study included 180 employees and 40 immediate leaders from 40 groups across 16 firms. To avoid of common methods of variances, multiple ratings were employed. Servant leadership of immediate team leaders and subordinates’ job satisfaction were rated by subordinates.

The results showed the positive relationship between perceived team leaders’ creating value for community (one dimension of servant leadership) and team members’ job satisfaction is strengthened by an increase in leaders’ deep-acting of emotions, but is decreased with an increase in leaders’ surface-acting and expression of naturally felt emotions.

This study confirms that a team leader’s emotional labor is likely to affect team members’ job satisfaction, which is also related to employees’ perceived servant leadership. Although how leaders display their emotions in organizations has a significant influence on the association between leaders’ creating value for community and subordinates’ job satisfaction, this study did not identify the explicit mechanisms to explain why this happens.

These findings will enrich the practice of leaders’ emotional management in organizations.

This chapter is the first to provide a perspective to understand leaders’ emotional labor from cross-level analysis. This study also extends our understandings of the effects of servant leadership and its relationships with subordinates’ job satisfaction through an exploration of each dimension of servant leadership on job satisfaction rather than relying on an overall measure servant leadership.

In this article, the authors aim to present the homotopy analysis method (HAM) for obtaining the approximate solutions of space‐time fractional differential equations with initial conditions.

The series solution is developed and the recurrence relations are given explicitly. The initial approximation can be determined by imposing the initial conditions.

The comparison of the HAM results with the exact solutions is made; the results reveal that the HAM is very effective and simple. The HAM contains the auxiliary parameter h, which provides a simple way to adjust and control the convergence region of series solution. Numerical examples demonstrate the effect of changing homotopy auxiliary parameter h on the convergence of the approximate solution. Also, they illustrate the effect of the fractional derivative orders a and b on the solution behavior.

The idea can be used to find the numerical solutions of other fractional differential equations.