Theoretical Analysis and Design Consideration of Advanced Linear Type Magnetic Flux Pump
As a current compensator, we already developed a linear type magnetic flux pump (LTMFP) that is comprised of DC coils, three phase armature coils, an LTS Nb foil and laminated linear slots. The LTMFP produced a homopolar traveling magnetic field with DC bias current and 3-phase armature current and then, a pumping current is generated in the closed superconducting loop. In this study, we have proposed an advanced LTMFP which can easily produce homopolar traveling magnetic field with the combination of a permanent magnet and the AC armature current. Since the permanent magnets have replaced DC coils in the system, its structure and operation are simplified. As well as, the heating loss of the advanced LTMFP is reduced due to the permanent magnet compared with the LTMFP. From this reason, we confirmed that the advanced LTMFP has more simplified and efficient operation compared with already developed magnetic flux pumps. This paper describes the structure and operating principle of the advanced LTMFP. As well as, the distributions of electromagnetic-thermal analysis of the LTS Nb foil were calculated based on the finite element method (FEM). Thus, in order to realize the homopolar traveling magnetic field, appropriately designing parameters of the combination of AC current and the permanent magnet were obtained.
Thermal Analysis of a Flux Pump With Simplified Conduction-Cooled Superconducting Magnet Model
A flux pump is one possible way to reduce the heat load of a superconducting magnet system by replacing mechanical connections with magnetic coupling. However, the heat loss of the flux pump should be analyzed so that it can be applied to conduction-cooled magnets because of the low temperature margin in conduction-cooled systems. In this paper, the simplified thermodynamic behavior of a linear-type flux pump system is investigated. The system is assumed to be cooled by a conduction cooling system. The heat generation of a linear-type flux pump is calculated based on the ac loss theory. The temperature stability of a thermal link for the flux pump system is analyzed with different design parameters. A design method is suggested for the thermal conductivity of the thermal link in a flux pump of conduction-cooled magnet by summarizing the results of the analysis.
The Origins of the Foundation Stories Genre in the Hebrew Bible and Ancient Eastern Mediterranean
This article examines two types of foundation narrative prevalent in the biblical literature in light of as-yet-undiscussed parallels from ancient Greek and Mediterranean texts. The first type, embodied in the Genesis narratives and Greek genealogical traditions, portrays the founders as leaving a distant land to settle peacefully in a new land. The second is exemplified by the central hexateuchal theme of the Israelites’ migration to Canaan by dispossessing the native population as well as the Dorian migration traditions. Several factors indicate that the foundation story genre also became central and foundational in other small kingdoms around the Mediterranean—as indicated, for example, by the Phoenician–Luwian inscriptions referring to bt Mpš/Mopsus and related classical sources. The popularity of the genre in the ancient Mediterranean is striking in light of the fact that, while experiencing tribal migrations and wanderings, the great Mesopotamian and Egyptian kingdoms never represented themselves as “immigrants.” It is suggested that this genre may have emerged with the rise of the new, small-scale kingdoms in the Mediterranean basin toward the end of the second millennium b.c.e. The Phoenician and Greek colonization enterprises of the first third of the first millennium b.c.e. in particular increased awareness of the newly emerging states and focused attention on ethnic identity.