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Real-Time Risk Assessment of Thyroid Function Abnormality using Irregularly-Sampled Heart Rate Records
No full textExhaustive Test Case Generation for Nuclear Safety Software Based on the Software Logic Model
No full textAn issue regarding the incorporation of software reliability within the nuclear power plant (NPP) probabilistic risk assessment model has emerged in the licensing processes of digitalized NPPs. Since software failure induces common-cause failure of the processor modules, the reliability of the software used in the NPP safety-critical instrumentation and control systems must be quantified and verified with proper test cases and environments. In this study, a software testing method based on the minimal cut set (MCS)???based exhaustive test case generation scheme is proposed where the software logic model is developed from available information on the software development and the MCSs that represent the necessary and sufficient conditions for the software variables??? states to produce safety software outputs are generated. The MCSs are then converted into the test cases, which can be used as inputs to the test bed to verify that the test cases produce correct outputs after software execution. The effectiveness of the proposed method is demonstrated with the safety-critical trip logic software of the APR-1400 reactor protection system. The method provides a systematic way to conduct exhaustive software testing and prove the functionality of the nuclear safety software based on the test result without uncertainties
A Three-Level Boost Converter With Fully State-Based Phase Selection Technique for High-Speed VCF Calibration and Smooth Mode Transition
No full textIn this article, a three-level current-mode boost converter with a fully state-based phase selection (FSPS) technique is presented. The proposed FSPS technique selects the operation phase adaptively to ensure the voltage across the flying capacitor (V-CF) to V-O/2 and changes the operation mode of a three-level boost converter (3L-BST). It enables the flying capacitor to be charged or discharged consecutively at the same duties every switching period and the operation mode to be changed smoothly. Therefore, 3L-BST improves the V-CF calibration speed with the stable startup and removes the sub-harmonic oscillation of the inductor current caused by the V-CF calibration, and the output voltage fluctuation is alleviated in the mode transition region. In addition, to compensate the stability of both valley and peak current-mode control for a wide output voltage range, the proposed FSPS technique adopts the adaptive slope generator (ASG) of which the slope can be changed from negative to positive. This work, fabricated in a 0.18-mu m bipolar-CMOSDMOS (BCD) process, occupies an area of 5.51 mm(2). The peak efficiency of the proposed 3L-BST is 95.3%, with an input range of 2-6 V, an output range of 5-32 V, and a 0.5-A maximum load current. The inductor current ripples are 1.45x smaller than prior VCF calibration techniques. The total startup time is 490 mu s
Uniform onset of the long proton bunch self-modulation seeded by an electron bunch in an overdense plasma
No full textThe phase, growth rate, and onset of long proton bunch self-modulation in plasma can be controlled by a preceding short charged particle bunch. In this paper, by analyzing the growth rates of the self-modulation obtained from particle-in-cell simulation results, we identify two modes of self-modulation, namely noise-seeded and externally seeded self-modulations, and investigate their onset timings. We find that a uniform onset of the self-modulation at each slice of the long proton bunch is crucial for fine-tuning its phase and amplitude. We then demonstrate that a low-energy and low-current electron seed bunch in overdense plasma generates near-axis radial wakefields similar to those observed in the blowout regime. Consequently, the resultant self-modulation is excited as a single mode simultaneously along the entire long proton bunch
Open Data from the Third Observing Run of LIGO, Virgo, KAGRA, and GEO
No full textThe global network of gravitational-wave observatories now includes five detectors, namely LIGO Hanford, LIGO Livingston, Virgo, KAGRA, and GEO 600. These detectors collected data during their third observing run, O3, composed of three phases: O3a starting in 2019 April and lasting six months, O3b starting in 2019 November and lasting five months, and O3GK starting in 2020 April and lasting two weeks. In this paper we describe these data and various other science products that can be freely accessed through the Gravitational Wave Open Science Center at https://gwosc.org. The main data set, consisting of the gravitational-wave strain time series that contains the astrophysical signals, is released together with supporting data useful for their analysis and documentation, tutorials, as well as analysis software packages
Microglial O-GlcNAcylation regulates inhibitory tone in the hippocampus via the Kv1.3 channel
No full textO- GlcNAcylation is a post-translational modification critical for various cellular functions such as regulation of gene
expression, signal transduction, and protein homeostasis. Notably, it has been shown that O-GlcNAcylation
modulates neuronal functions through "on-demand" protein modification. Despite this fact, it remains to be
determined whether O-GlcNAcylation is essential for glial cells. In this study, we generated microglia-specific OGlcNAc
transferase (OGT) knockout (KO) mice to reveal the physiological roles of microglial O-GlcNAcylation in the
brain. We found that the loss of O-GlcNAcylation in microglia alters the innate biology. Interestingly, the potassium
channel Kv1.3, which is known to be O-GlcNAcylated, exhibited an elevated expression level and channel
conductance in hippocampal OGT cKO microglia. We also found that these Kv1.3 abundant microglia specifically
modulate hippocampal GABAergic synapses and inhibitory tone, causing a shift in E/I balance. Collectively, these
data demonstrate that microglia are important for tuning inhibitory tone in the hippocampus via O-GlcNAcylation of
the microglial proteins including the Kv1.3 channel
A 701.7 TOPS/W Time-Domain Spiking Neural Network Compute-in-Memory Processor with 9T1C Bitcell
No full textA highly energy-efficient compute-in-memory (CIM) processor for a low-power spiking neural network (SNN) is proposed in this paper. Most previous CIM processors were limited to binary neural networks with poor accuracy. Other CIM processors for multi-bit precision convolutional neural networks were developed to increase the accuracy, but they showed low energy efficiency. In addition, most previous works suffered from a power-hungry analog-to-digital converter (ADC) for partial sum computation. They consumed lots of energy due to the current-mode or voltage-mode analog computations. To resolve the issues, we propose a Time-Domain SNN CIM (TS-CIM) processor with 9T1C bitcell for highly energy-efficient time-domain computation with a compact area. The proposed Time multiply-and-accumulate circuit removes ADC that consumes a large portion of the system energy. In addition, the Analog Precision Reconstruction Unit is introduced for multi-bit reconstruction of the phase-coded input activations of SNN. Thanks to pipelined architecture, TS-CIM enables execution of the whole convolution layers without wasted cycles for the stall. The proposed TS-CIM is designed with 65 nm CMOS logic technology and achieves 701.7 TOPS/W energy efficiency
An extremely energetic cosmic ray observed by a surface detector array
No full textCosmic rays are energetic charged particles from extraterrestrial sources, with the highest-energy events thought to come from extragalactic sources. Their arrival is infrequent, so detection requires instruments with large collecting areas. In this work, we report the detection of an extremely energetic particle recorded by the surface detector array of the Telescope Array experiment. We calculate the particle???s energy as (~40 joules). Its arrival direction points back to a void in the large-scale structure of the Universe. Possible explanations include a large deflection by the foreground magnetic field, an unidentified source in the local extragalactic neighborhood, or an incomplete knowledge of particle physics
