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PurposeThe purpose of the paper is to report on research in cultural differences in decision‐making styles in project teams composed of team members from different nationalities. Differences in decision making in mainly German teams vs mainly Swedish teams was assessed.Design/methodology/approachA sequential mixed‐method approach was used, starting with interviews to develop a grounded theory, followed by survey to test the theory. Factor and regression analyses allowed for identification of the cultural antecedents of the identified differences in decision making.FindingsLocus of control differences in decision making were identified, together with factors for differences in decisions, namely decision‐making style, process, and involvement. Correlated cultural antecedents to these factors, in the form of personal attributes, were found.Research limitations/implicationsAlthough the research design provides for some credibility of the results, the scope of the study is limited mainly to the engineering and construction industry in the two countries.Practical implicationsThe study helps team members and project managers to understand the impact of their cultural differences on decision‐making process and style. Through that the study helps to minimize the potential friction when working on multicultural projects. Recommendations for practitioners are provided.Originality/valueThe idiosyncrasies of decision making in multicultural projects are researched using the example of Sweden and Germany. A model is built which extends existing project management theory. The paper also provides insights into the lived experiences of practicing project managers in multicultural teams and gives hints on how to overcome cultural barriers.

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Summary The ability of helicopters to hover and land vertically has spurred an interesting field of research on the development of autonomous flight for these rotatory wing aircrafts. Linear control theory with gain scheduling, which is based on linearizing the system at the equilibrium points, dominated the helicopter autopilot design. Unlike the linear cascaded autopilot structure used in the existing literature, this paper uses state‐dependent linear like structure, including rate‐limited actuator dynamics, with cascaded autopilot topology. This approach allows nonlinear control laws to be implemented throughout the entire flight envelope, providing satisfactory robustness and stability over the various parameter uncertainties and time delays. The cascaded autopilot topology with nonlinear dynamical equations contains a new sliding sector control (SSC) mechanism which is derived for multi‐input nonlinear dynamical systems. The proposed SSC structure for multi‐input nonlinear systems is used in the inner loop of the cascaded autopilot system where the fastest dynamics are required to be controlled for rapid changes in the helicopter dynamical characteristics which enables one to stabilize the helicopter over a wide range of flight conditions. The proposed cascaded autopilot topology with the new SSC mechanism is tested in simulations to assess its robustness and stability properties. To establish its feasibility, the proposed control method is replaced with a suboptimal control method, namely state‐dependent differential Riccati equation (SDDRE) method, for the inner loop and the results of the proposed control architecture are compared with those of SDDRE method.

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Time delays, parameter uncertainties, and disturbances are the fundamental problems that hinder the stability and reduce dramatically the tracking performance of dynamical systems. In this paper, a new state-dependent nonlinear time-varying sliding mode control autopilot structure is proposed to cope with these dynamical and environmental complexities for an unmanned helicopter. The presented technique is based on freezing the nonlinear system equations on each time step and designing a controller using the frozen system model at this time step. The proposed method offers an improved performance in the presence of major disturbances and parameter uncertainties by adapting itself to possible dynamical varieties without a need of trimming the system on different operating conditions. Unlike the existing linear cascade autopilot structure, this study also proposes a nonlinear cascade state-dependent coefficient helicopter autopilot structure consisting of four separate nonlinear sub-systems. The proposed method is tested through the real time and PC-based simulations. To show the performance of the proposed robust method, it is also bench-marked against a linear sliding control control in PC-based simulations.