Turbo Message Passing Based Burst Interference Cancellation for Data Detection in Massive MIMO-OFDM Systems

This paper investigates the fundamental data detection problem with burst interference in massive multiple-input multiple-output orthogonal frequency division multiplexing(MIMO-OFDM) systems. In particular, burst interference may occur only on data symbols but not on pilot symbols, which means that interference information cannot be premeasured. To cancel the burst interference, we first revisit the uplink multi-user system and develop a matrixform system model, where the covariance pattern and the low-rank property of the interference matrix is discussed. Then, we propose a turbo message passing based burst interference cancellation(TMP-BIC) algorithm to solve the data detection problem, where the constellation information of target data is fully exploited to refine its estimate. Furthermore, in the TMP-BIC algorithm, we design one module to cope with the interference matrix by exploiting its lowrank property. Numerical results demonstrate that the proposed algorithm can effectively mitigate the adverse effects of burst interference and approach the interference-free bound.

Vector Approximate Message Passing with Sparse Bayesian Learning for Gaussian Mixture Prior

Compressed sensing(CS)aims for seeking appropriate algorithms to recover a sparse vector from noisy linear observations.Currently,various Bayesian-based algorithms such as sparse Bayesian learning(SBL)and approximate message passing(AMP)based algorithms have been proposed.For SBL,it has accurate performance with robustness while its computational complexity is high due to matrix inversion.For AMP,its performance is guaranteed by the severe restriction of the measurement matrix,which limits its application in solving CS problem.To overcome the drawbacks of the above algorithms,in this paper,we present a low complexity algorithm for the single linear model that incorporates the vector AMP(VAMP)into the SBL structure with expectation maximization(EM).Specifically,we apply the variance auto-tuning into the VAMP to implement the E step in SBL,which decrease the iterations that require to converge compared with VAMP-EM algorithm when using a Gaussian mixture(GM)prior.Simulation results show that the proposed algorithm has better performance with high robustness under various cases of difficult measurement matrices.

Hybrid simulation of q=1 high-order harmonics driven by passing energetic particles in tokamak plasmas

High-order harmonics q(ψ_(s))=1 energetic particle modes(EPMs)have been observed in toroidal plasmas experiments with neutral beam injection.To investigate these phenomena,linear properties and nonlinear dynamics of these EPMs driven by passing energetic particles(EPs)are studied via the global hybrid kinetic-magnetohydrodynamic code M3D-K.Simulation results demonstrate that passing EPs'effects on high mode-number harmonics(q(ψ_(s))=m/n=2/2,3/3,4/4)instability are more obvious than the q(ψ_(s))=1/1 mode,especially when q-profile is sufficiently flat in the core region.Furthermore,the effects of the pitch angleΛ_0 and beam ion pressure P_(hot)/P_(total)on the features of high n components are also analyzed specifically.It is found that there exists only one resonant condition for these EPMs.In the nonlinear phase,these high mode-number harmonics can induce significant energetic ions redistribution and chirping up phenomena,which differs from the classical fishbone excited by passing EPs.These discoveries are conducive to better apprehend the underlying physical mechanisms of the highorder harmonics driven by passing EPs.

China Mourns Passing Of Jiang Zemin

A memorial for Jiang Zemin,who passed away on November 30,2022,at the age of 96,was held on December 6,2022,at the Great Hall of the People in Beijing.President Xi Jinping addressed the meeting.In a eulogy delivered at the memorial,Xi attributed the tremendous achievements of the Party and the nation between 1989 and 2002 to the late Chinese leader’s eminence and bold vision,the key role he played,and his superb political leadership.

基于RFieldbus的Token-Passing协议实时性能建模

RFieldbus 无线现场总线的 MAC 协议 Token Passing 可看成是一个多台多队列排队系统。在分析了 TTR(令牌目的循环时间)对 RFieldbus 中 3 个优先级队列的服务时间的动态限制后,多台单队列排队模型 RF-P 被提出。对从站的轮巡交换数据任务被转化为RF-P 中的令牌内走步时间,原有的高、低级别两个队列则化成了两个具有不同 Poisson 到达率的 M/G/1/∞服务台。利用排队论中的准守恒 PCL 定律,在将服务时间限制转换为数量限制后,求出了等待响应时间的数学解析式。与试验结果的比较表明,在负载不大于 60%时其偏差度约在 10-20%间。

An MPI parallel DEM-IMB-LBM framework for simulating fluid-solid interaction problems

The high-resolution DEM-IMB-LBM model can accurately describe pore-scale fluid-solid interactions,but its potential for use in geotechnical engineering analysis has not been fully unleashed due to its prohibitive computational costs.To overcome this limitation,a message passing interface(MPI)parallel DEM-IMB-LBM framework is proposed aimed at enhancing computation efficiency.This framework utilises a static domain decomposition scheme,with the entire computation domain being decomposed into multiple subdomains according to predefined processors.A detailed parallel strategy is employed for both contact detection and hydrodynamic force calculation.In particular,a particle ID re-numbering scheme is proposed to handle particle transitions across sub-domain interfaces.Two benchmarks are conducted to validate the accuracy and overall performance of the proposed framework.Subsequently,the framework is applied to simulate scenarios involving multi-particle sedimentation and submarine landslides.The numerical examples effectively demonstrate the robustness and applicability of the MPI parallel DEM-IMB-LBM framework.

Static Analysis Techniques for Fixing Software Defects in MPI-Based Parallel Programs

The Message Passing Interface (MPI) is a widely accepted standard for parallel computing on distributed memorysystems.However, MPI implementations can contain defects that impact the reliability and performance of parallelapplications. Detecting and correcting these defects is crucial, yet there is a lack of published models specificallydesigned for correctingMPI defects. To address this, we propose a model for detecting and correcting MPI defects(DC_MPI), which aims to detect and correct defects in various types of MPI communication, including blockingpoint-to-point (BPTP), nonblocking point-to-point (NBPTP), and collective communication (CC). The defectsaddressed by the DC_MPI model include illegal MPI calls, deadlocks (DL), race conditions (RC), and messagemismatches (MM). To assess the effectiveness of the DC_MPI model, we performed experiments on a datasetconsisting of 40 MPI codes. The results indicate that the model achieved a detection rate of 37 out of 40 codes,resulting in an overall detection accuracy of 92.5%. Additionally, the execution duration of the DC_MPI modelranged from 0.81 to 1.36 s. These findings show that the DC_MPI model is useful in detecting and correctingdefects in MPI implementations, thereby enhancing the reliability and performance of parallel applications. TheDC_MPImodel fills an important research gap and provides a valuable tool for improving the quality ofMPI-basedparallel computing systems.

Glia-to-neuron reprogramming to the rescue?

Over the last two decades,the dogma that cell fate is immutable has been increasingly challenged,with important implications for regenerative medicine.The brea kth rough discovery that induced pluripotent stem cells could be generated from adult mouse fibroblasts is powerful proof that cell fate can be changed.An exciting extension of the discovery of cell fate impermanence is the direct cellular reprogram ming hypothesis-that terminally differentiated cells can be reprogrammed into other adult cell fates without first passing through a stem cell state.

Train-induced aerodynamic characteristics of vertical sound barriers influenced by several factors

Investigations into the aerodynamic properties of vertical sound barriers exposed to high-speed operations employ computational fluid dynamics.The primary focus of this research is to evaluate the influence of train speed and the distance(D)from the track centerline under various operating conditions.The findings elucidate a marked elevation in the aerodynamic effect amplitude on sound barriers as train speeds increase.In single-train passages,the aerodynamic effect amplitude manifests a direct relationship with the square of the train speed.When two trains pass each other,the aerodynamic amplitude intensifies due to an additional aerodynamic increment on the sound barrier.This increment exhibits an approximate quadratic correlation with the retrograde train speed.Notably,the impact of high-speed trains on sound barrier aerodynamics surpasses that of low-speed trains,and this discrepancy amplifies with larger speed differentials between trains.Moreover,the train-induced aerodynamic effect diminishes significantly with greater distance(D),with occurrences of pressure coefficient(CP)exceeding the standard thresholds during dual-train passages.This study culminates in the formulation of universal equations for quantifying the influence of train speed and distance(D)on sound barrier aerodynamic characteristics across various operational scenarios.

Preface

This focused issue of the Communications on Applied Mathematics and Computation is dedicated to the memory of Professor Ching-Shan Chou,who passed away in November 2021.With her passing,our community of applied mathematicians lost not only a brilliant researcher but also a cherished friend and colleague.

An End-To-End Hyperbolic Deep Graph Convolutional Neural Network Framework

Graph Convolutional Neural Networks(GCNs)have been widely used in various fields due to their powerful capabilities in processing graph-structured data.However,GCNs encounter significant challenges when applied to scale-free graphs with power-law distributions,resulting in substantial distortions.Moreover,most of the existing GCN models are shallow structures,which restricts their ability to capture dependencies among distant nodes and more refined high-order node features in scale-free graphs with hierarchical structures.To more broadly and precisely apply GCNs to real-world graphs exhibiting scale-free or hierarchical structures and utilize multi-level aggregation of GCNs for capturing high-level information in local representations,we propose the Hyperbolic Deep Graph Convolutional Neural Network(HDGCNN),an end-to-end deep graph representation learning framework that can map scale-free graphs from Euclidean space to hyperbolic space.In HDGCNN,we define the fundamental operations of deep graph convolutional neural networks in hyperbolic space.Additionally,we introduce a hyperbolic feature transformation method based on identity mapping and a dense connection scheme based on a novel non-local message passing framework.In addition,we present a neighborhood aggregation method that combines initial structural featureswith hyperbolic attention coefficients.Through the above methods,HDGCNN effectively leverages both the structural features and node features of graph data,enabling enhanced exploration of non-local structural features and more refined node features in scale-free or hierarchical graphs.Experimental results demonstrate that HDGCNN achieves remarkable performance improvements over state-ofthe-art GCNs in node classification and link prediction tasks,even when utilizing low-dimensional embedding representations.Furthermore,when compared to shallow hyperbolic graph convolutional neural network models,HDGCNN exhibits notable advantages and performance enhancements.

Apolipoprotein A-I binding protein-mediated neuroprotection in glaucomatous neuroinflammation and neurodegeneration

Glaucoma is a multifactorial eye disorder that can cause vision loss and irreversible blindness,affecting individ uals aged 40 to 80 yea rs worldwide.Due to the aging population,it is expected that the number of people affected by glaucoma will surpass 111 million by 2040 as the disease becomes more prevalent.Glaucoma primarily contributes to optic nerve axon loss and the progressive degeneration of retinal ganglion cells (RGCs),subsequently leading to vision impairment.

Enhanced Steganalysis for Color Images Using Curvelet Features and Support Vector Machine

Algorithms for steganography are methods of hiding data transfers in media files.Several machine learning architectures have been presented recently to improve stego image identification performance by using spatial information,and these methods have made it feasible to handle a wide range of problems associated with image analysis.Images with little information or low payload are used by information embedding methods,but the goal of all contemporary research is to employ high-payload images for classification.To address the need for both low-and high-payload images,this work provides a machine-learning approach to steganography image classification that uses Curvelet transformation to efficiently extract characteristics from both type of images.Support Vector Machine(SVM),a commonplace classification technique,has been employed to determine whether the image is a stego or cover.The Wavelet Obtained Weights(WOW),Spatial Universal Wavelet Relative Distortion(S-UNIWARD),Highly Undetectable Steganography(HUGO),and Minimizing the Power of Optimal Detector(MiPOD)steganography techniques are used in a variety of experimental scenarios to evaluate the performance of the proposedmethod.Using WOW at several payloads,the proposed approach proves its classification accuracy of 98.60%.It exhibits its superiority over SOTA methods.

两组不同中医体质安氏Ⅱ^(1)错(牙合)患者运用PASS技术矫正前后牙颌相关指标及体质的变化

目的:比较平和质与阴虚质安氏Ⅱ1错(牙合)患者运用PASS矫正技术治疗后牙颌及体质相关指标的变化。方法:选择2019年2月-2023年2月来笔者医院口腔科就诊的安氏Ⅱ类1分类患者为研究对象,通过体质分型选择平和质(10例)与阴虚质(10例)错(牙合)患者运用PASS矫正技术进行治疗,比较两组患者矫正时托槽的脱落情况,矫正前后面型、牙颌及体质的改变。结果:平和质组患者托槽的脱落率明显小于阴虚质组(P<0.05);两种体质患者运用PASS矫正技术治疗前后的头影测量结果差异有统计学意义(P<0.05);矫正结束半年后,阴虚质较平和质患者的体质发生了明显改善(P<0.05)。结论:相较于阴虚体质错(牙合)患者,平和质体质错(牙合)患者在托槽脱落情况及矫正结束后体质的转归方面具有明显优势,因此不同体质对于错(牙合)畸形的矫正具有一定的指导意义。

Cholesky分解的单Pass随机算法

对于大规模数据矩阵,数据的读取成本远高于算法本身的成本;对存储在磁盘外部的流型数据,往往只有一次读取数据的机会。而以往的Cholesky分解的随机算法都至少需要读取输入数据两次,难以满足实际应用中的低成本需求。本文基于矩阵分解的单pass随机算法研究,提出了Cholesky分解的单pass随机算法,并给出了该算法的误差上界,最后通过数值实验验证了该算法的可行性以及有效性。

EMBRACING THE SILVER ECONOMY

China is home to the world’s largest aging population.According to data of the seventh national census,the number of people aged 60 and above is 264.02 million,accounting for 18.70 percent of Chinese population.The Ministry of Civil Affairs forecasts that China's senior population will exceed 300 million during the 14th Five-Year Plan period(2021-2025),passing from a mildly aging society to a moderately aging society.

DECODING THE VITALITY OF CHINA’S ECONOMY

With its GDP surpassing RMB 126 trillion,per capita disposable income increasing by 6.1 percent,and 12.44 million urban jobs created,China saw brisk economic recovery last year.These achievements reflect the sound fundamentals of its economy,particularly given the shrinking global trade and increasing geopolitical frictions.

Going Green and Smart

Two sets of energy data from China have received widespread attention recently:the share of renewable energy in China’s total installed power generation capacity climbed to 53.8 percent in the first half of this year,after surpassing thermal power’s share last year;and in July,China’s new-energy vehicles outsold fuel-powered passenger cars on a monthly basis for the first time.The two breakthroughs have once again brought China’s push for green transformation to the fore.

Investing in the Future

Foreign investors confident of the Chinese market despite Western media’s“foreign capital leaving China”rhetoric.WHILE the world economy faced multiple challenges and had a slow recovery in 2023,China’s GDP grew by 5.2 percent,surpassing the growth of many leading economies.China’s robust growth and commitment to high-quality development and high-standard opening-up will continue to provide new opportunities for foreign investors.

New Energy Indeed

According to data released on January 11 by the China Association of Automobile Manufacturers(CAAM),China’s automobile production and sales volumes both surpassed 30 million for the first time in 2023,hitting a new record.Notably,the new energy vehicle(NEV)sector has seen significant growth.In 2023,exports of Chinese NEVs exceeded 1.2 million units,notching a year-on-year increase of 77 percent.