ABSTRACT
Hyperloop is a new concept of ground transportation. In Hyperloop, travelling occurs in near-vacuum tubes under 0.001 atm at a subsonic speed of up to 1200 km/h. During acceleration to and driving at a subsonic speed, magnetic levitation is employed. Thus far, various levitation technologies in existing high-speed maglev trains have been considered. Among those technologies, superconducting (SC) electrodynamic suspension (EDS) is a highly effective levitation system for Hyperloop owing to its advantages of a large levitation gap, levitation stability, and control being unnecessary. However, analyzing an EDS system requires the electromagnetic transient analysis of complex three-dimensional (3D) features, and its computational load generally limits the use of numerical methods, such as the 3D finite element method (FEM) or dynamic circuit theory. In this study, a novel model that can rapidly and accurately calculate the frequency-dependent equivalent inductance was developed. The developed model was then applied to design an EDS system using the decoupled resistance-inductance equations of levitation coils. Next, levitation coils of SC-EDS were designed and analyzed for use in Hyperloop. The obtained results were compared with the FEM results to validate the developed model. In addition, the model was experimentally validated by measuring currents induced by moving pods.
ABSTRACT
There are several studies that show that large amounts of acrylamide are detected in Jerusalem artichoke (Helianthus tuberosus L.) tea. This study examined acrylamide, inulin content and antioxidant properties of Jerusalem artichoke tea brewed in different conditions. Uniformly sliced Jerusalem artichokes were soaked in different salt and acidic solutions for 60 min at 20 °C and extracted with hot or cold water. The acrylamide content was analyzed by high-performance liquid chromatography-tandem mass spectrometry. The Inulin content and antioxidant activity were analyzed by spectrophotometer. Soaking significantly reduced acrylamide levels (p < 0.05) with the largest decrease observed for acetic acid, whereas the effects of all soaking treatments on inulin content were similar. Teas brewed using small-particle-size samples and hot water exhibited the highest acrylamide/inulin levels and antioxidant activity. Consequently, The most suitable treatment for Jerusalem Artichoke tea preparation was 1-h soaking in 1% acetic acid at 20 °C.
