Key Engineering Materials Vol. 698

Abstract: In this paper, we proposed a phase-change memory (PCM) structure which has a ring confined chalcogenide (RCC) for reducing reset operation current. The temperature distributions of normal bottom contact (NBC), confined chalcogenide (CC) and proposed RCC PCMs were simulated by 3 dimensional finite element method. It was very clear that a much higher temperature can be obtained for RCC than NBC cell at a certain programming current. The programming characteristics also exhibited that the operation current of RCC cell can be as low as about 45% of NBC cell while that of CC cell was about 82% of CC cell.

Abstract: A real-time position detection system is developed for measuring heavy ions with low fluence and energy of several hundred MeV, which are generated from an azimuthally varying field (AVF) cyclotron accelerator. We investigate the photoluminescence of α-Al₂O₃ single crystals implanted with Eu (Al₂O₃:Eu), which is used in the detection system. The Al₂O₃:Eu scintillators with a fluence of 3.0 × 10¹⁶ cm⁻² are annealed at 500–900°C. The annealing conditions required for the Al₂O₃:Eu scintillators to obtain the maximum luminescence are 0.5 h at 600°C. The scintillator is placed on the AVF cyclotron target stage under atmospheric pressure and is irradiated by 260-MeV Ne. An inverted confocal microscope with a ×10 objective lens is positioned behind the Al₂O₃:Eu scintillator, and the luminescent images during ion irradiation are obtained by a position-sensitive camera unit with a 512 × 512 pixel electron multiplying charge-coupled device. The images indicate that our online measurement system has a sufficient spatial resolution, since the luminous diameter induced by irradiation with 190 ions /s is almost the same as that of the microbeam.

Abstract: A radio-photoluminescence (RPL) dosimeter with a copper-ion luminescent center was fabricated to evaluate its response in ionized particle detection. A focused proton microbeam with varying energies up to 3 MeV and heavy ions of 490 MeV osmium (Os) were employed along with X-rays to evaluate its performance in micrometer-scale radiation monitoring. The response to ionized particles was evaluated under focused proton beam irradiation where the peak wavelength differed from that obtained under X-ray irradiation. Two peaks were observed under Os irradiation where the secondary-generated particles and photons have a significant effect on the dosimeter. The results suggest that the fabricated RPL dosimeter with copper luminescence center could be used to estimate the irradiation effect of primary ionized particles separately from the effects of secondary particles, photons, and environmental background radiation.

Abstract: The development of a low-cost noninvasive motion capture device for use in physiotherapy clinics and as a diagnostic tool attracts enormous attention. In this study, we aimed to investigate the feasibility of medical and healthcare applications of the Kinect v2 motion capture devices based on practical medical needs. In particular, we developed three applications: a non-contact respiration monitoring system for the diagnosis of COPD, a rehabilitation assistance system, and a three-dimensional skeletal motion viewer system.