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Resistive memories are affected by significant error rates tied to structural relaxation and wear out of the resistive memory devices. A way to reduce the need for strong error-correcting codes (ECCs) is to improve error correction based on the weak bits, i.e., potentially faulty bits, identified in sensed memory words. Here, it is formally proven that conventional ECC decoders reinforced with weak-bit-flipping may achieve similar error correction capability as theoretical generalized-minimum-distance decoders. It is shown that weak-bit-flipping may reduce the uncorrectable bit error rate (UBER) by orders of magnitude when applied in conjunction with single-error-correcting and double-error-detecting (SEC-DED) or double-error-correcting and triple-error-detecting (DEC-TED) codes. In particular, weak-bit-information extracted from a 2T2R memory and used to reinforce a DEC-TED code with a conventional decoder may enable an UBER that is one order of magnitude better than the UBER achieved with a triple-error-correcting (TEC) code and a conventional decoder. • A conventional errors-only decoder with weak-bit-flipping can outperform an erasures-and-errors decoder • A conventional errors-only decoder with weak-bit-flipping can outperform a generalized-minimum-distance decoder • The impact of weak-bit-flipping on error correction is estimated starting from resistance state distributions • The formalism used to estimate the efficiency of weak-bit-flipping is independent of the weak-bit-identification scheme [ABSTRACT FROM AUTHOR]

Eighteen error field correction coils (EFCCs) consisting of copper conductor and epoxy resin are installed in the vacuum vessel of JT-60SA in order to correct magnetic fields caused by manufacturing and installation errors of superconducting coils. The EFCCs are supported by pedestals made of stainless steel 316 L, and the pedestal has spring bars made of NCF625. The pedestals need to withstand electromagnetic force induced by EFCC current and magnetic field during plasma operations. They also need to allow relative displacement between the EFCC and the vacuum vessel during baking operations caused by the temperature difference between the vacuum vessel of 200 °C and EFCC of 40 °C. Diameter of the spring bars and connection structure for fixing the spring bars were designed through FEM analysis. [ABSTRACT FROM AUTHOR]