In the blockchain, consensus mechanism plays a key role in maintaining security and legitimation of contents recorded blocks. Various blockchain mechanisms have been proposed. However, there is no technical analysis comparison as guideline to determine which type should be adopted specific scenario/application. To this end, work investigates three mainstream namely, Proof Work (PoW), Stake (PoS), Direct Acyclic Graph (DAG), identifies their performances terms average time generate new block,...

Abstract Parallel excitation has been introduced as a means of accelerating multidimensional, spatially‐selective using multiple transmit coils, each driven by unique RF pulse. Previous approaches to pulse design in parallel were either formulated the frequency domain or restricted echo‐planar trajectories, both. This paper presents an approach that is quadratic optimization problem spatial and allows use arbitrary k ‐space trajectories. Compared approaches, new method some important...

Abstract Parallel transmitter techniques are a promising approach for reducing B 1 inhomogeneity due to the potential adjusting spatial excitation profile with independent RF pulses. These may be further improved transmit sensitivity encoding (SENSE) methods because information in pulse design provides an that is inherently compensated inhomogeneity. This paper presents proof of this concept using SENSE 3D tailored pulses designed small flip angles. An eight‐channel receiver coil was used...

Abstract Current standard sensitivity‐encoded parallel imaging (SENSE) utilizes a fully sampled low‐resolution reference scan to estimate the coil sensitivities. This adds time and may introduce misregistration artifacts. The purpose of this study was investigate feasibility estimating sensitivities for spiral SENSE directly from an undersampled k ‐space center. limited spatial frequencies sensitivities, undersampling beyond Nyquist radius cause image A point spread function (PSF) analysis...

A phase demodulation strategy based on the Kalman filter for sinusoidal encoders is proposed in this article. For state equation and observation constructed model, angle, angular speed, speed fluctuation are system states, sine cosine signals output by encoder observations. In addition, due to nonlinear relationship between observations function linearized extended approach. order implement hardware platform with a field programmable gate array (FPGA), matrix model of further derived into an...

Abstract Contrast‐enhanced magnetic resonance angiography (CE‐MRA) requires high spatial resolution to demonstrate detailed vasculature and temporal capture the contrast bolus. Sparse bright voxels in MRA permit substantial undersampling MRI data acquisition, allowing simultaneous resolution. We developed a time‐resolved 3D technique using efficient spiral sampling trajectory, performed off‐resonance corrections inhomogeneity field maps. View sharing sliding window reconstruction were...

Particulate matter 2.5 (PM2.5) is a growing concern worldwide due to its association with respiratory diseases, including chronic obstructive pulmonary disease (COPD). Stemonine, traditional Chinese herb, has been demonstrated exhibit anti-inflammatory and antioxidant properties, making it potential drug for the treatment of diseases. The therapeutic effects stemonine on mice PM2.5-induced COPD were investigated in present study. Kunming randomly divided into following five groups...

Abstract A new k ‐space direct matrix inversion (DMI) method is proposed here to accelerate non‐Cartesian SENSE reconstructions. In this a global equation established on basic MRI principles, and the inverse of encoding found from set local equations by taking advantage small extension coil maps. The DMI algorithm's efficiency achieved reloading precalculated when maps trajectories remain unchanged, such as in dynamic studies. Phantom human subject experiments were performed 1.5T scanner...

Abstract Purpose: To develop a simple correction approach to mitigate shading in 3 Tesla (T) breast MRI. Materials and Methods: A slightly modified receive (Rx) array, which we termed field shaping array (FSA), was shown at 3T. In this FSA, one Rx element selectively unblocked tuned off the Larmor frequency during transmit (Tx) phase. The current flowing Tx created secondary field; vector addition of directly by body coil resulted more uniform excitation profile over entire area. returned...

This study investigates the effect of surface roughness on diffraction efficiency two-dimensional gratings. Firstly, a model was constructed using FDTD, followed by significant analysis ridge roughness, groove and sidewall efficiency. Then, impact each type studied separately. Results indicate that has negative efficiency, whereas have positive When ridge, groove, coexist, decreases with an increase in consistent previous research. However, under conditions minimal actually increases....

A two-dimensional grating interferometer with the nanometer accuracy is proposed, which employs a transmissive diffraction and corner cube prism in its optical configuration. The distinctive features of this path configuration are as follows: (i) Fourfold subdivision achieved based on principle secondary diffraction, enhancing capability. (ii) utilization enables parallel retroreflection diffracted light, facilitating ease alignment. Utilizing period 4 µm (resulting an signal 1 after...

Abstract Multivariate time series are widely used in industrial equipment monitoring and maintenance, health monitoring, weather forecasting other fields. Due to abnormal sensors, failures, environmental interference human errors, the collected multivariate usually have certain missing values. Missing values imply regularity of data, seriously affect further analysis application series. Conventional imputation methods such as statistical machine learning-based cannot learn latent...

Interrupt technology is a key for processors to respond external events and plays an important role in the embedded field. The open source RISC-V architecture defines complete set of interrupt mechanisms with hardware definitions that do not support nesting systems only machine mode, software adds additional time overhead. This paper based on mechanism defined by RISC-V, using state control global enablement processor nesting, save site restore through stacking out-stacking avoid consumption...

Since the present backwardness of pump-jack fault diagnosis method and waste time labor, we adopt wavelet network to transform working current pump-jacks get detail coefficient then make it characteristics. To adjust parameters neural network, self-tuning learning rate conjugated gradient optimize object function. The application on thirty five indicates that this can be used with accuracy over ninety percent.

A high-factor interpolation method based on space-time modulation and a Kalman filter for optical encoders is proposed. Space-time employs reference time signal to modulate the output displacement of encoder into signal. Subsequently, high-frequency pulse signals are used interpolation, which detect phase obtain information from output. The factor this depends frequencies signal, independent moving speed. employed estimate velocity, compensating lag errors in by improve real-time performance...

High performance infrared lens used in aerospace optical remote sensing systems have great benefit resource exploration, pollution monitoring etc. However the high technical threshold of manufacture, production and launch cost due to heavy materials, long period alignment restricted its use especially for civil commercial aerospace. Here we present a realization mass production. An unique opto-mechanical structure design has been implemented order meet requirements space lens. Some...