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The authors propose a semiparametric approach for testing independence between two infinite-order cointegrated vector autoregressive series (IVAR(∞)). The procedures considered can be viewed as extensions of classical methods proposed by Haugh (1976, JASA) and Hong (1996b, Biometrika) for testing independence between stationary univariate time series. The tests are based on the residuals of long autoregressions, hence allowing for computational simplicity, weak assumptions on the form of the underlying process, and a direct interpretation of the results in terms of innovations (or shocks). The test statistics are standardized versions of the sum of weighted squares of residual cross-correlation matrices. The weights depend on a kernel function and a truncation parameter. Multivariate portmanteau statistics can be viewed as a special case of our procedure based on the truncated uniform kernel. The asymptotic distributions of the test statistics under the null hypothesis are derived, and consistency is established against fixed alternatives of serial cross-correlation of unknown form. A simulation study is presented which indicates that the proposed tests have good size and power properties in finite samples.

The need for sensors and actuators is an important issue in the field of smart textiles and garments. Important developments in sensing and heating textile elements consist in using non‐metallic yarns, for instance carbon containing fibres, directly in the textile fabric. Another solution is to use electro‐conductive materials based on conductive polymer composites (CPCs) containing carbon or metallic particles. The purpose of this paper is to describe research based on the use of a carbon black polymer composite to design two electro‐conductive elements: a strain sensor and a textile heating element.

The composite is applied as a coating consisting of a solvent, a thermoplastic elastomer, and conductive carbon black nanoparticles. In both applications, the integration of the electrical wires for the voltage supply or signal recording is as discreet as possible.

The CPC materials constitute a well‐adapted solution for textile structures: they are very flexible, and thus do not modify the mechanical characteristics and general properties of the textile structure.

In the case of the heating element, the use of metallic yarns as electrodes makes the final structure a more rigid. This can be improved by choosing other conducting yarns that are more flexible, or by developing knitted structures instead of woven fabrics.

The CPC provide a low cost solution, and the elements are usually designed so as to work with a low voltage supply.

The CPC has been prepared with a solvent process which is especially adapted to flexible materials like textiles. This is original in comparison to the conventional melt‐mixing process usually found in literature.

Risk management (RM) is a rapidly developing field in France. Several associations are trying to promote an approach of ERM that is far removed from insurance and compliance. In practice, we note that the RM in French companies is still very strongly rooted in internal control. Risk managers in France do not have yet the “risk champion” role of the chief risk officer.

The author argues that contemporary college culture is predicated on hedonism indicated by a use of predominantly social time in which parties, alcohol, casual sex, and lax academics pervade students' experiences. Coincident with this culture, however, is a deleterious pattern among students that has developed dramatically: their compromised mental health. The situation presents an apparent paradox: why are many students suffering when enveloped by fun? This chapter draws a connection between fun and suffering by treating each as conditions that spring from the sociohistorical context that situates institutions of higher education. In so doing, a theory is set forth to explain why despair is rendered applicable and how it is institutionally installed in the minds of modern-day college students.

The purpose of this study is to apply an incompressible smoothed particle hydrodynamics (ISPH) method to simulate the Magnetohydrodynamic (MHD) free convection flow of a nanofluid in a porous cavity containing rotating hexagonal and two circular cylinders under the impacts of Soret and Dufour numbers.

The inner shapes are rotating around a cavity center by a uniform circular motion at angular rate ω. An inner hexagonal shape has higher temperature T_h and concentration C_h than the inner two circular cylinders in which the temperature is T_c and concentration is C_c. The performed numerical simulations are presented in terms of the streamlines, isotherms and isoconcentration as well as the profiles of average Nusselt and Sherwood numbers.

The results indicated that the uniform motions of inner shapes are changing the characteristics of the fluid flow, temperature and concentration inside a cavity. An augmentation on a Hartman parameter slows down the flow speed and an inclination angle of a magnetic field raises the flow speed. A rise in the Soret number accompanied by a reduction in the Dufour number lead to a growth in the concentration distribution in a cavity.

ISPH method is used to simulate the double-diffusive convection of novel rotating shapes in a porous cavity. The inner novel shapes are rotating hexagonal and two circular cylinders.

The purpose of this paper is to analyze the different mediating processes by which authentic leadership and transformational leadership on the part of local union representatives influence members’ union citizenship behaviors (UCB) (i.e. UCBO and UCBI). Drawing from the social learning perspective, the authors suggest that authentic and transformational forms of leadership are associated with UCB through specific mechanisms i.e. member-representative value congruence and members’ collectivist orientation, respectively.

This research adopts a cross-sectional design. Structural equation modeling and bootstrap analysis were used to test the hypotheses among 343 members of a Canadian union federation representing professionals in the education sector.

The results show that the influence of authentic leadership on UCB is explained through value congruence and the influence of transformational leadership is principally exerted through members’ collectivist orientation.

By enhancing the understanding of the behavioral manifestations of local union leadership and its influential mechanisms, this research offers interesting avenues for union organizations that wish to develop and implement leadership training programs at the local level.

Only a handful of studies have investigated the relational antecedents of UCB, such as leadership. This research thus contributes to the UCB literature by extending the spectrum of examined local union leaders’ behaviors.

The purpose of this study is to investigate the Dynamics of micropolar – water B Fluids flow simultaneously under the influence of thermal radiation and Soret–Dufour Mechanisms.

The thermal radiation contribution, the chemical change and heat generation take fluidity into account. The flow equations are used to produce a series of dimensionless equations with appropriate nondimensional quantities. By using the spectral homotopy analysis method (SHAM), simplified dimensionless equations have been quantitatively solved. With Chebyshev pseudospectral technique, SHAM integrates the approach of the well-known method of homotopical analysis to the set of altered equations. In terms of velocity, concentration and temperature profiles, the impacts of Prandtl number, chemical reaction and thermal radiation are studied. All findings are visually shown and all physical values are calculated and tabulated.

The results indicate that an increase in the variable viscosity leads to speed and temperature increases. Based on the transport nature of micropolar Walters B fluids, the thermal conductivity has great impact on the Prandtl number and decrease the velocity and temperature. The current research was very well supported by prior literature works. The results in this paper are anticipated to be helpful for biotechnology, food processing and boiling. It is used primarily in refrigerating systems, tensile heating to large-scale heating and oil pipeline reduction.

All results are presented graphically and all physical quantities are computed and tabulated.

This paper aims to investigate the effect of Powell–Eyring fluid induced by a stretched sheet. Heat and mass transfer under the influence of magnetic dipole over a stretching sheet are taken into account.

Nonlinear coupled governing equations are solved using the optimal homotopy asymptotic technique, and a computer software package BVPh 2.0 is used for numerical computations.

Impact of significant quantities is graphically examined. It is seen that the heat transfer deceases for higher values of viscous dissipation parameter, radiation parameter, Dufour number, whereas it increases for bigger values of Prandtl number. The numerical results have been validated through comparison with existing literature as a special case of proposed model and perceived that the Soret number has reining role to increase the rate of heat transfer.

To the best of the authors’ knowledge, this study is reported for the first time.

In this paper, we studied the steady flow of a radiative magnetohydrodynamics viscoelastic fluid over an exponentially stretching sheet. This present work incorporated the effects of Soret, Dufour, thermal radiation and chemical reaction.

An appropriate semi-analytical technique called homotopy analysis method (HAM) was used to solve the resulting nonlinear dimensionless boundary value problem, and the method was validated numerically using a finite difference scheme implemented on Maple software.

It was observed that apart from excellence agreement with the results in literature, the results obtained gave further insights into the behaviour of the system.

The purpose of this research is to investigate heat and mass transfer profiles of a MHD viscoelastic fluid flow over an exponentially stretching sheet in the influence of chemical reaction, thermal radiation and cross-diffusion which are hitherto neglected in previous studies.