Study of quench propagation properties in Rutherford-type cables

筑波大学University of Tsukuba博士（工学）Doctor of Philosophy in EngineeringQuench propagration velocity is one of the most important parameters for quench protection of superconducting magnets. A larger quench propagation velocity is preferable in order to prevent local temperature from being increased significantly. In a multi-strand cable whose strands are individually insulated, it has been reported that the quench propagation velocity increases by a current redistribution between strands. However, influences of current redistribution on a quench velocity for a cable made of non-insulated strands have not been studied. We examined the relations between the current redistribution and the quench propagation velocity in a Rutherford cable made of non-insulated strands. Measurements were performed in the cables with three contact conditions between strands, and it was found that the quench propagatin velocity and the current redistributions depended on the contact conditions between strands. A measurement was also performed in the cable without polyimide tape for the cable insulation, and we found that the polyimide tape also influenced on the quench propagation velocity. A numerical simulation of current redistribution using a simple model was performed. We made comparisons between the test and the numerical results, and there was good agreement each other. We analyzed the numerical results in detail, and we found that the current redistribution occurred around the quench front caused the incerase of the quench propagation velocity.1999Includes bibliographical references (p. 97-101)doctoral thesi

Observation of B+ → χc0K+

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Two-Channel Bilateral Control of Delta Robots with Gravity Compensation

This paper presents three-dimensional bilateral delta robots based on a novel transfer-function-based two-channel bilateral control system. This configuration has proven to provide better control perfomance while only requiring two channels of communication, for position information exchange, as opposed to the traditional four-channel bilateral control method. The proposed three-dimensional bilateral Delta robot architecture proves to have good performance, however it is affected by gravity, and therefore, in order to ensure smooth operation of the delta robots we introduce a compensation for gravity on the bilateral control system, based on the analysis of the kinematics of the delta configuration. In this paper, we discuss the application of transfer-function-based two-channel bilateral control to three-dimensional delta robots, and the accuracy improvement obtained by the application of gravity compensation to the two-channel bilateral control.journal articl

Fundamental Problems in Agricultural Policy

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Mechanical Evaluation of Novel High-Strength Lightweight Concrete with Core-Shell Structured Lightweight Aggregate

Core-shell structured aggregates (CSA) offer a promising approach to lightweight concrete to reduce density, en- hance sustainability, and improve thermal insulation but face challenges such as stress concentration, poor interfacial bonding, and manufacturing limitations. This study investigates the critical factors influencing the performance of CSA-based lightweight concrete, including morphology, size, quantity, shell thickness, spatial distribution, and ma- terial composition. Based on this investigation, a novel capsule-shaped CSA (CCSA) was developed and evaluated through concrete compression experiments and finite element analysis. The steel-based lightweight concrete achieved a 16–19 % density reduction (1811–1879 kg/m3) while retaining 82–92 % of the compressive strength (32.6–36.8 MPa) of conventional concrete. For the PLA-based variants achieved a lower density (1383 kg/m3) but reduced strength (11.16 MPa), highlighting material-dependent trade-offs. The capsule design’s optimized geometry and sur- face treatments enhanced interfacial bonding and stress distribution, demonstrating its viability for structural applica- tions requiring lightweight and high-strength concrete.journal articl

Correlation between food intake and body weight gain for all animals except those in the two recovery groups

<p><b>Copyright information:</b></p><p>Taken from "Effect of an herbal extract Number Ten (NT) on body weight in rats"</p><p>http://www.cmjournal.org/content/2/1/10</p><p>Chinese Medicine 2007;2():10-10.</p><p>Published online 14 Sep 2007</p><p>PMCID:PMC2034566.</p><p></p