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Because of the various geometric descriptions of different bearing types, performance calculation of journal bearing is complicated, and is difficult in traditional model. This paper aims to simplify the calculation of the journal bearing performance, and to reduce the workload.

On the basis of previous research, a general performance calculation model of journal bearing is proposed in this paper. Eccentricity ratio and attitude angle of axis to each pad are calculated by coordinates of spindle center and each pad center by establishing the unified coordinate system. The surface deformation of journal bearing is taken into consideration, and a correction value is added to the dimensionless oil film thickness.

The performance calculation results of various fix-pad and tilting-pad journal bearings match the results of the existing references very well, revealing the validity of the model. The general model can greatly reduce programming workload, and increase adaptability to different bearings.

Geometric descriptions of both fix-pad and tilting-pad journal bearings are unified in this model, which can be applied to both standard and non-standard journal bearings with different preload ratios. In addition, due to the unification of different bearings types, this model is more conducive to performance comparison among different bearing types, and promotes the development of new structural forms for journal bearings.

The purpose of this paper is to present a transition detector (TD)-based radiation hardened flip-flop (TDRH-FF) for single event upset (SEU).

With SEU recovery and single event transient (SET) detector mechanism, the TDRH-FF can tolerate SEU during hold mode and generate a warning signal for architecture-level recovery during transport mode when input signal contains SET. Evaluation results show that the TDRH-FF outperforms comparable comprehensive performance.

Simulation results show that 1) the mean pulse width of the correction glitches (at full width half maximum) of TDRH-FF is less than 10 ps; 2) the area overhead of TDRH-FF is similar to the EVFERST-FF, BISER-FF and DNURHL-FF; 3) TDRH-FF has the same average power consumption as SETTOF, and moderate PDP and Ps values among these compared FFs.

In this paper, a TD-based TDRH-FF is proposed to solve the problems in the previous design. And the main contributions of the proposed TDRH-FF are summarized: Minimum size transistors are used in the proposed TD which leads to a considerable decrease in area overheads and propagation delay (resulting in an ignorable correction glitch); and compared with other radiation hardened flip-flop, TDRH-FF outperforms comparable comprehensive performance.