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Realistic data bank of aerodynamic and stability derivatives is still missing for hybrid buoyant aerial vehicles. Such vehicles take-off and land similar to an aircraft with their partial weight balanced by the aerostatic lift. The purpose of this paper is to use wind tunnel testing for a better understanding of the aerodynamic and static stability behavior of such vehicles.

The effect of wing on the aerodynamic and static stability characteristics of a clean configuration hybrid buoyant is analyzed. The free stream velocity is 20 m/s, and ranges of angle of attack and side slip angle are from −8° to 12° and ±16°, respectively. Data are corrected to account for the effect of strut interference and zero load condition. The maximum blockage of the model with respect to the cross-section area of the test section is about 2.7 per cent.

A hybrid model manufactured by using wood and metal is an optimum solution with less number of parts. The vehicle is statically, longitudinally and directionally stable. Wings designed to fulfill the partial requirement of lift contribute significantly to counter the huge moment generated by the voluminous hull for centre of gravity location ahead of the leading edge of the wing.

There are number of manufacturing constraints for scaling down a model of a hybrid buoyant aerial vehicle configuration. Specially, the thickness of the wing limits the testing envelop of angle of attack and free stream velocity.

The data presented here are a preliminary guide for further work on larger size models. The data may also be used to build and perform flight tests on small full-scale instrumented models and to obtain flight dynamics data.

The estimated aerodynamic and stability derivatives and slopes can be utilized in future for multidisciplinary design.

To develop a high‐order compact finite‐difference method for solving flow problems containing shock waves.

A numerical algorithm based on high‐order compact finite‐difference schemes is developed for solving Navier‐Stokes equations in two‐dimensional space. The convective flux terms are discretized by using advection upstream splitting method (AUSM). The developed method is then used to compute some example laminar flow problems. The problems considered have a range of Mach number that corresponds to subsonic incompressible flow to hypersonic compressible flows that contain shock waves and shock/boundary‐layer interaction.

The paper shows that the AUSM flux splitting and high‐order compact finite‐difference methods can be used accurately and robustly in resolving shear layers and capturing shock waves. The highly diffusive nature of conventional flux splitting especially on coarse grids makes them inaccurate for boundary layers even with high‐order discretization.

This paper presents a high‐order numerical method that can accurately and robustly capture shock waves without deteriorating oscillations and resolve boundary layers and shock/boundary layer interaction.

A high‐order compact upwind algorithm is developed for solving Navier‐Stokes equations in two‐space dimensions. The method is based on advection upstream splitting method and fourth‐order compact finite‐difference schemes. The convection flux terms of the Navier‐Stokes equations are discretized by a compact cell‐centered differencing scheme while the diffusion flux terms are discretized by a central fourth‐order compact scheme. The midpoint values of the flux functions required by the cell‐centered compact scheme are determined by a fourth‐order MUSCL approach. For steady‐state solutions; first‐order implicit time integration, with LU decomposition, is employed. Computed results for a laminar flow past a flat plate and the problem of shock‐wave boundary layer interaction are presented.

The paper aims to compute rolling moments on a follower aircraft wing due to vortices generated by a plain and flapped NACA4412 wing using experimental particle image velocimetery (PIV) data.

This paper describes the detailed variation of the induced rolling moment on a follower aircraft wing derived from a PIV velocity field measurement. A rectangular wing of a subsonic wall interference model is used as a vortex generator in two different configurations: plain wing of NACA4412 cross‐section profile; and flapped wing with trailing edge flap of NACA0012 cross‐section profile extended at 20°.

Results obtained showed that the maximum induced rolling moment coefficient depends on the strength of the vortex produced by the generating aircraft wing and increases linearly with the increment of the angle of attack.

This paper provides an insight on the effects of different angles of attacks for plain and flapped wings on the induced rolling moment coefficient and therefore, the hazard imposed on the following aircraft can be estimated.

Assuming that corporate social responsibility (CSR) is “a process of accumulating knowledge and experience” (Tang et al., 2012, p. 1298), this paper aims to investigate whether and how CSR knowledge (Asif et al., 2013; Kim, 2017) affects financial performance in the European banking industry.

The empirical research analyses a panel of 72 banks from 20 European countries over seven years (2009-2015). The hypotheses were tested using fixed effects regression analysis and the two-stage Heckman model (1976) to address endogeneity bias.

The findings of this work are twofold. First, consistent with the concept of knowledge absorptive capacity (Cohen and Levinthal, 1990), the internal CSR of banks (Kim et al., 2010) positively affects citizenship performance (Peterson, 2004a). Second, in line with the reputational effect of CSR (Margolis et al., 2009; Bushman and Wittenberg-Moerman, 2012), citizenship performance is a positive predictor of a bank’s financial performance.

From a knowledge-based perspective, the analysis shows that accrued internal CSR knowledge plays a key role in implementing effective CSR programs for external stakeholders. Moreover, this study shows how CSR engagement in external initiatives can improve a bank’s competitiveness because of the relationship between citizenship performance and the positive reputation of a bank.

The management of CSR initiatives may favor the sharing of knowledge and creation of trust relationships among banks and internal and external stakeholders. CSR knowledge contributes to expanded value creation for both society and banks.

The knowledge management perspective of CSR provides new insights into the sustainability of banks’ business models and contributes to advancing the debate on the governance modes and effects of CSR. Moreover, the CSR perspective offers additional opportunities for addressing the challenges associated with sharing tacit knowledge within and outside of organizations.