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The purpose of this paper is to present a reversible flux linkage model of the switched reluctance motor so that the rotor position can be computed analytically.

The presented flux linkage model uses a Fermi function like equation with four coefficients to fit flux linkage characteristics. In this work, the coefficients are calculated from flux‐current‐angle data using numerical curve fitting with the least squares method. A rotor position model is then derived by inverting the flux linkage model. With a simple estimation scheme based on the rotor position model, the rotor position is estimated continuously. Simulation and experiments are then performed to verify the proposed method.

The presented flux linkage model agrees well with flux linkage characteristics. The average absolute relative error (AARE) of the model varies between 0.3 per cent and 5.3 per cent. With the derived rotor position model, rotor position can be estimated conveniently for either steady or dynamic operations.

The simulation and experimental results indicate that the presented model is an eligible candidate for applications such as rotor position estimation, performance simulation and other model based controls.

Unlike previously reported methods, the presented flux linkage model is reversible so that a rotor position model can be derived and the rotor position can be computed analytically.

The purpose of this paper is to investigate the extent to which interdisciplinary (HASS, i.e. non-STEM) factors—in particular, accounting, stakeholder management and accountability—enable, influence and motivate large human exploration ventures, principally in maritime and space fields, utilizing Columbus’s and Chinese explorations of the 1400s as the primary setting.

The study analyzes archival data from narrative and interpretational history, including both academic and non-academic sources, that relate to two global historical events, the Columbus and Ming Chinese exploration eras (c. 1400–1500), as a parallel to the modern “Space Race”. Existing studies on pertinent HASS (Humanities and Social Sciences) and STEM (Science, Technology, Engineering and Mathematics) enablers, influencers and motivators are utilized in the analysis. The authors draw upon the concepts of stakeholder theory and the construct of accountability in their analysis.

Findings suggest that non-STEM considerations—politics, finance, accountability, culture, theology and others—played crucial roles in enabling Western Europe (Columbus) to reach the Americas before China or other global powers, demonstrating the pivotal importance of HASS factors in human advancements and exploration.

In seeking to answer those questions, this study identifies only those factors (HASS or STEM) that may support the success or failure in execution of the exploration and development of a region such as the New World or Space. Moreover, the study has the following limitation. Relative successes, failures, drivers and enablers of exploratory ventures are drawn almost exclusively from the documented historical records of the nations, entities and individuals (China and Europe) who conducted those ventures. A paucity of objective sources in some fields, and the need to set appropriate boundaries for the study, also necessitate such limitation.

It is observable that many of those HASS factors also appear to have been influencers in modern era Space projects. For Apollo and Soyuz, success factors such as the relative economics of USA and USSR, their political ideologies, accountabilities and organizational priorities have clear echoes. What the successful voyages of Columbus and Apollo also have in common is an appetite to take risks for an uncertain return, whether as sponsor or voyager; an understanding of financial management and benefits measurement, and a leadership (Isabella I, John F. Kennedy) possessing a vision, ideology and governmental apparatus to further the venture’s goals.

Whilst various historical studies have examined influences behind the oceangoing explorations of the 1400s and the colonization of the “New World”, this article takes an original approach of analyzing those motivations and other factors collectively, in interdisciplinary terms (HASS and STEM). This approach also has the potential to provide a novel method of examining accountability and performance in modern exploratory ventures, such as crewed space missions.