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It has been recently shown that diffusion of dopant during doping of inhomogeneous structure could be accelerated or decelerated in comparison with diffusion of dopant in structure with averaged diffusion coefficient. As a continuation of previous work, the purpose of this paper is to introduce an approach of estimating the limited value of acceleration of the dopant diffusion by choosing the dependence of the dopant diffusion coefficient on the coordinates.

The authors analyzed relaxation of concentration of dopant during diffusion in inhomogeneous material. The authors determine conditions for maximal acceleration and deceleration of diffusion of dopant. The authors introduced analytical approach for analysis of dopant diffusion in inhomogeneous material.

The authors determine conditions for maximal acceleration and deceleration of diffusion of dopant.

It has been shown that dopant diffusion could be decelerated essentially to a greater extent, rather than accelerated.

Empirical studies show substantial variation across immigrants in the rate and direction of assimilation along various dimensions (e.g., cross-ethnic contact, language, identity). To explain this variation, past research has focused on identifying exogenous factors, such as discrimination, human capital, and settlement intention. In this chapter we argue that variation in immigrant outcomes emerges endogenously through positive interaction effects between dimensions of assimilation. We propose a new assimilation model in which processes of social influence and selection into congruent social environments give rise to multiple long-term equilibria. In this model, migrants who are already assimilated along many dimensions tend to also adapt along other dimensions, while less assimilated migrants become more strongly embedded in their ethnic group.

To test the assimilation model, we derive a number of hypotheses, which we evaluate using trend analysis and dynamic panel regression on data from the Longitudinal Survey of Immigrants to Canada.

The data mostly confirm the hypotheses, providing overall support for the assimilation model.

Our theory and findings suggest that immigrants would follow divergent assimilation trajectories even in the absence of a priori population heterogeneity in external factors.

The positive interaction effects between cultural and structural dimensions of assimilation suggest that mixed policies that promote integration while seeking to prevent loss of identity go against the natural tendency for cultural and structural assimilation to go hand in hand.

The present chapter proposes a novel model of immigrant assimilation and an empirical test.

The purpose of this paper is to focus on the process of knowledge transfer within social networks composed of a pool of experts, and newcomers whose aim is primarily to acquire new knowledge, such as communities of practice. The authors wish to understand which communication system and which information about others' knowledge should be provided to get to a better diffusion of knowledge.

Agent‐based models and social network analysis are used and many simulations are run, in which communication mode and information about others' knowledge are varied.

Results emphasize the part played by newcomers in the process of direct knowledge transfer. They constitute additional sources of knowledge and act as intermediaries. Results also show that in a process of indirect transfer of knowledge, they have only little influence on the process of individual learning. These results enable the authors to formulate some recommendations to facilitate knowledge transfer within a knowledge intensive community. Non‐hierarchical structures of communication should be preferred and the participation of newcomers in the activities of the community fully encouraged.

This paper combines agent‐based modelling and social networks analysis to investigate the field of knowledge transfer and enables the identification of the key elements in the process of knowledge diffusion within a community of practice. It thus provides some solution to eventual congestion problems in the access to the knowledge held within the community.

The purpose of this study is to perform a detailed review on the numerical modeling of multiphase and multicomponent flows in microfluidic system using phase-field method. The phase-field method is of emerging importance in numerical computation of transport phenomena involving multiple phases and/or components. This method is not only used to model interfacial phenomena typical to multiphase flows encountered in engineering and nature but also turns out to be a promising tool in modeling the dynamics of complex fluid-fluid interfaces encountered in physiological systems such as dynamics of vesicles and red blood cells). Intrinsically, a priori unknown topological evolution of interfaces offers to be the most concerning challenge toward accurate modeling of moving boundary problems. However, the numerical difficulties can be tackled simultaneously with numerical convenience and thermodynamic rigor in the paradigm of the phase field method.

The phase-field method replaces the macroscopically sharp interfaces separating the fluids by a diffuse transition layer where the interfacial forces are smoothly distributed. As against the moving mesh methods (Lagrangian) for the explicit tracking of interfaces, the phase-field method implicitly captures the same through the evolution of a phase-field function (Eulerian). In contrast to the deployment of an artificially smoothing function for the interface as used in the volume of a fluid or level set method, however, the phase-field method uses mixing free energy for describing the interface. This needs the consideration of an additional equation for an order parameter. The dynamic evolution of the system (equation for order parameter) can be described by Allen–Cahn or Cahn–Hilliard formulation, which couples with the Navier–Stokes equation with the aid of a forcing function that depends on the chemical potential and the gradient of the order parameter.

In this review, first, the authors discuss the broad motivation and the fundamental theoretical foundation associated with phase-field modeling from the perspective of computational microfluidics. They subsequently pinpoint the outstanding numerical challenges, including estimations of the model-free parameters. They outline some numerical examples, including electrohydrodynamic flows, to demonstrate the efficacy of the method. Finally, they pinpoint various emerging issues and futuristic perspectives connecting the phase-field method and computational microfluidics.

This paper gives unique perspectives to future directions of research on this topic.

Examines the tenth published year of the ITCRR. Runs the whole gamut of textile innovation, research and testing, some of which investigates hitherto untouched aspects. Subjects discussed include cotton fabric processing, asbestos substitutes, textile adjuncts to cardiovascular surgery, wet textile processes, hand evaluation, nanotechnology, thermoplastic composites, robotic ironing, protective clothing (agricultural and industrial), ecological aspects of fibre properties – to name but a few! There would appear to be no limit to the future potential for textile applications.

Nonlinear mixed-convective entropy optimized the flow of hyperbolic-tangent nanofluid (HTN) with magnetohydrodynamics (MHD) process is considered over a vertical slendering surface. The impression of activation energy is incorporated in the modeling with the significance of nonlinear radiation, dissipative-function, heat generation/consumption connection and Joule heating. Research in this area has practical applications in the design of efficient heat exchangers, thermal management systems or nanomaterial-based devices.

Suitable set of variables is introduced to transform the PDEs (Partial differential equations) system into required ODEs (Ordinary differential equations) system. The transformed ODEs system is then solved numerically via finite difference method. Graphical artworks are made to predict the control of applicable transport parameters on surface entropy, Bejan number, Sherwood number, skin-friction, Nusselt number, temperature, velocity and concentration fields.

It is noticed from present numerical examination that Bejan number aggravates for improved estimations of concentration-difference parameter a_2, Eckert number E_c, thermal ratio parameter ?_w and radiation parameter R_d, whereas surface entropy condenses for flow performance index n, temperature-difference parameter a_1, thermodiffusion parameter N_t and mixed convection parameter ?. Sherwood number is enriched with the amplification of pedesis-motion parameter N_b, while opposite development is perceived for thermodiffusion parameter. Lastly, outcomes are matched with formerly published data to authenticate the present numerical investigation.

To the best of the authors' knowledge, no investigation has been reported yet that explains the entropic behavior with activation energy in the flowing of hyperbolic-tangent mixed-convective nanomaterial due to a vertical slendering surface.

This paper aims at understanding the causes of low adoption of hybrid rice technology. The paper also assesses the impact of adoption of hybrids and modern varieties on crop yield, vis-à-vis the old or traditional varieties.

Using unit-level data from a large-scale survey of farm households (19,877 paddy cultivators), the authors applied multi-nomial regression method to understand the factors for adoption of hybrid rice and instrumental variable method of regression to estimate its impact.

The findings demonstrate that in India, hybrid rice is often grown on relatively poor soils, resulting in greater irrigation costs and for other inputs, such as fertilizers. Further, farmers' poor access to information on the traits of hybrid rice and the associated agronomic practices, as well as poor access to financial resources, hampers efforts to scale up its adoption. More importantly, the findings reveal that the relative yield advantage of hybrids over open-pollinated modern varieties is not large enough to incentivize the rapid adoption of hybrid rice technology.

Given the higher cost of hybrids than the inbred varieties, enhancing paddy cultivators' access to financial resources can accelerate the adoption of hybrid rice in India.

The study is based on unit level data from a large-scale, nationally representative survey of farm households, comprising a sample of 19,877 paddy cultivators, spread across states in India.

The aim of this study is to present numerical analyses for combined effects of the inlet temperature (ΔT⁺) and the wall‐to‐fluid thermal capacitance ratio (a*) on the laminar mixed convection unsteady flows in a vertical pipe.

The full Navier‐Stokes and energy, coupled, unsteady state, two‐dimensional governing equations for ascending laminar mixed convection in a vertical pipe are solved numerically using a finite‐difference scheme.

The results show that the thermohydraulic flow behaviour is highly dependent on both parameters (ΔT⁺, a*). Moreover, the unsteady characteristics of the flow can involve oscillatory and reversed flow phenomena yielding the unstable flows. For the heating case, the reversed flow appears below the wave instability and the unsteady vortex is always significant in the vicinity of the wall, whatever ΔT⁺ and a*<100. For the cooling case, the reversed flow appears in the central region of the pipe; it develops on top of the wave instability.

This study should be very useful to improve heat transfer equipment.

The paper shows clearly the combined effects of both parameters (ΔT⁺, a*) on the laminar mixed convection flow.

The fast and flexible development of fast switching electromagnetic valves as used in modern gasoline engine demands the availability of efficient and accurate simulation tools. The purpose of this paper is to provide an enhanced computational scheme of these actuators including all relevant physical effects of magneto‐mechanical systems and including contact mechanics.

The finite element (FE) method is applied to efficiently solve the arising coupled system of partial differential equations describing magneto‐mechanical systems. The algorithm for contact mechanics is based on the cross‐constraint method using an energy‐ and momentum‐conserving time‐discretisation scheme. Although solving separately for the electromagnetic and mechanical system, a strong coupling is ensured within each time step by an iterative process with stopping criterion.

The numerical simulations of the full switching cycle of an electromagnetic direct injection valve, including the bouncing during the closing state, are just feasible with an enhanced and robust mechanical contact algorithm. Furthermore, the solution of the nonlinear electromagnetic and mechanical equations needs a Newton scheme with a line search scheme for the relaxation of the step size.

The paper provides a numerical simulation scheme based on the FE method, which includes all relevant physical effects in magneto‐mechanical systems, and which is robust even for long‐term contact periods with multitude re‐opening phases.

Electric fields (EFs) are known to influence cell and tissue activity. This influence can be due to thermal or non-thermal effects. While the non-thermal effects are still matter of discussion, thermal effects might be detrimental for cell and tissue viability due to thermal damage, this fact being exploited by applications like hyperthermia and tissue ablation. The paper aims to discuss these issues.

In this work the authors investigate the influence of thermal damage in the consolidation of bone formation during electrostimulation (ES). The authors introduce a mathematical model describing the migration of osteoprogenitor cells, the thermal variation, the thermal damage accumulation and the formation of new bone matrix in an injury (fracture) site.

Numerical results are in agreement with experimental data and show that EFs more intense than 7.5 V/cm are detrimental for the viability of osteoprogenitor cells and the formation of new bone.

The model is suitable to conduct dosimetry studies in support of other different ES techniques aimed at improving bone and soft tissues repair.