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To address the issue of the high cost of GaN substrates, a recycling process for GaN substrates using a laser slicing technique was investigated. The channel properties of lateral MOSFETs and the reverse characteristics of vertical PN diodes, which represent the main components of vertical power devices, exhibited no degradation either before and after laser slicing or due to the overall GaN substrate recycling process. This result indicates that the proposed recycling process is an effective method for reducing the cost of GaN substrates and has the potential to encourage the popularization of GaN vertical power devices.

The collision accident in collegiate football game was simulated based on the game video and the concussive impact on the head was analyzed. First, the collision motion of players was reproduced based on the video by using motion analysis, and the translational and rotational velocities, relative position and contact location of the struck and the striking players’ heads just before the collision were calculated. Then the data obtained were input to two helmeted finite element (FE) human head models as the initial condition, and the brain injury risk was evaluated by using the impact analysis. The FE helmet model was validated by a drop test of the helmet in which the head impactor was embedded. In the present study, two concussion suspected accident cases were analyzed; then the concussion was evaluated by ten mechanical parameters generated inside the skull caused by the collision. The injury risk evaluated by multi parameters belonged to the dangerous range that may cause concussion and was consistent with the diagnosis of the medical team doctor. The brain injury risk can be successfully estimated by the reconstructed simulation of the game video and FE analysis. To our knowledge, this study is the first attempt in Japan to estimate the brain injury risk systematically by a combination of game video analysis which is originally introduced for the players’ health care and FE analysis by helmeted human head model. In the future, brain injury risk caused by an accident can be evaluated with higher accuracy by analyzing more accident cases.

We develop priors for Bayes estimation of quantum states that provide minimax state estimation. The relative entropy from the true density operator to a predictive density operator is adopted as a loss function. The proposed prior maximizes the conditional Holevo mutual information, and it is a quantum version of the latent information prior in classical statistics. For one qubit system, we provide a class of measurements that is optimal from the viewpoint of minimax state estimation.

Our objective is to analyze both tensional and bending stress of bolted joints under eccentric load. Especially, our analysis is under four combined conditions as described below, (1) embedded bolted joints, (2) thinner clamped plate, (3) large eccentric load, (4) permitting partial separation. Those combined conditions include some difference between ours and previous researches. The partial separation easily occurs at structural interfaces under those combined conditions, and both stresses sharply increase due to the propagation of the separation. That is the reason why it is very important to consider the effect of partial separation. There are many analytical methods based on numerical calculations or FEM analysis, however, there is no numerical calculation method, which is justly applicable under those combined conditions. We apply Faulhaber method proposed in VDI2230 and develop our original method considering the bolt axial loads, which are composed of both bolt's deflection and deflection angle as beam. Numerical calculations on the above-mentioned and experiments and elastic FEM analysis based on three dimensional contact theory were conducted. The results about our method's correlation against experiments and FEM analysis are shown in this report.

Introduction: The trunk flexor endurance test (TFET) has been used with variations in the inclination angle from 45 to 60 degrees. Specifically, an inclination angle of 60 degrees is deemed suitable for older adults, yet may be overly simplistic for athletes. The clinical relevance of TFET could differ based on the inclination angle and populations. Objectives: This study aims to investigate the association between different TFET angles and trunk performance. Study Design: A correlational analysis approach. Methods: The participants consisted of 350 physical education students (236 men, 114 women), divided into three groups based on angles (45, 50, and 55 degrees). The TFET commenced by moving the backrest 10 cm backwards at the designated angle while participants maintained the initial posture. The test concluded when participant's back contacted the backrest again. Trunk performance was evaluated through 30-second speed sit-ups, trunk extensor endurance test (TEET), closed kinetic chain upper extremity stability test (CKCUEST), and upper quarter Y balance test (UQYBT). Results: Among men, a significant difference was noted between 45 and 55 degrees, whereas no significant difference was observed among women across angles. For men, correlation analysis revealed significant associations between TFET and sit-ups (r=.32 with 45 degrees, r=.37 with 50 degrees, r=.27 with 55 degrees), TEET (r=.54 with 50 degrees), and UQYBT (r=.30 with 55 degrees). For women, significant correlations were observed between TFET and sit-ups (r=.49 with 45 degrees, r=.61 with 55 degrees), TEET (r=.38 with 45 degrees), CKCUEST (r=.35 with 45 degrees, r=.31 with 50 degrees), and UQYBT (r=-.37 with 55 degrees). Conclusions: Our findings showed that the angle of TFET influences both the endurance capacity and the outcomes on trunk performance tests. The variation in TFET duration across different angles underscores the importance of selecting appropriate angles to accurately assess the physical fitness levels of diverse populations. [ABSTRACT FROM AUTHOR]

We consider a series of configurations defined by fibers of a given base configuration. We prove that Markov degree of the configurations is bounded from above by the Markov complexity of the base configuration. As important examples of base configurations we consider incidence matrices of graphs and study the maximum Markov degree of configurations defined by fibers of the incidence matrices. In particular we give a proof that the Markov degree for two-way transportation polytopes is three. [ABSTRACT FROM AUTHOR]