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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.

The purpose of this research is to ascertain the feasibility of fabricating polymer optical fibers (POFs) based textile structures by knitting with Polymethylmethacrylate (PMMA) based optical fibers for textile sensor application. It has long been established that by using the principles of physics, POFs have the capability to function as sensors, detecting strain, temperature and other variables. However, POF applications such as strain and pressure sensing using knitting techniques has since not been very successful due to a number of reasons. Commercially available PMMA-based optical fibers tend to be fragile and susceptible to breakages when subjected to stress during the knitting processes. Also light transmitted within these fibers is prone to leakage due to the curvature that results when optical fibers are interlaced or interlooped within fabric structures.

Using Stoll’s multi-gauge CMS 350 HP knitting machine, five fabric structures namely, 1 × 4 float knit structure, tunnel inlay knit structure, 3:1 fleece fabric and 2:1 fleece fabric structure respectively were used to knit sensor samples. The samples were subsequently tested for length of illumination and sensitivity relative to applied pressure.

The results of this preliminary study establish that embedding plastic optical fibers into a knitted structure during the fabric formation process for soft strain sensor application possible. The best illumination performance was recorded for tunnel inlay structure which had an average of 94 cm course length of POF being illuminated. Sensor sensitivity experiments also establish that the relative spectral intensity of the fiber is sensitive to both light and pressure. Problems encountered and recommendations for further research have also been discussed and proffered.

Due to resource limitations, an innovative technique (use of precision weight set) was used to apply pressure to the sensors. Consequently, information regarding the extent of corresponding sensor deformation has not been used in this initial analysis.

Because the fundamental step toward finding a solution to any engineering problem is the acquisition of reliable data, and considering the fact that most of the popular technologies used for soft textile sensors are still bedeviled with the problem of signal instability and noise, the success of this application thus has the tendency to promote the wide spread adoption of POF sensors for smart apparel applications.

As far as research on soft strain sensors is concerned, to the best of the authors’ knowledge, this is the first study to have attempted to knit deformable sensors using commercially available POFs.