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High Order IMEX Stochastic Galerkin Schemes for Linear Transport Equation with Random Inputs and Diffusive Scalings

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Communications on Applied Mathematics and Computation 2024年第1期6卷 325-339页

作者： Zheng Chen Lin mu Department of Mathematics University of Massachusetts Dartmouth285 Old Westport RoadDartmouth02747MAUSA Department of Mathematics University of GeorgiaAthens30602GAUSA

In this paper,we consider the high order method for solving the linear transport equations under diffusive scaling and with random *** tackle the randomness in the problem,the stochastic Galerkin method of the generalized polynomial chaos approach has been ***,the high order implicit-explicit scheme under the micro-macro decomposition framework and the discontinuous Galerkin method have been *** provide several numerical experiments to validate the accuracy and the stochastic asymptotic-preserving property.

关键词： Stochastic Galerkin scheme linear transport equations generalized polynomial approach stochastic asymptotic-preserving property

Study of 26 Galactic Open Clusters with Extended Main-sequence Turnoffs

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Research in Astronomy and Astrophysics 2024年第6期24卷 28-37页

作者： Yang-Yang Deng Zhong-mu Li Yunnan Observatories Chinese Academy of SciencesKunming 650216China University of Chinese Academy of Sciences Beijing 100049China Institute of Astronomy and Information Dali UniversityDali 671003China

Recent studies indicate that some Galactic open clusters(OCs)exhibit extended main-sequence turnoff(eMSTO)in their color–magnitude diagrams(CMDs).However,the number of Galactic OCs with eMSTO structures detected so far is limited,and the reasons for their formation are still *** work identifies 26 Galactic OCs with undiscovered eMSTOs and investigates the causes of these *** population types and fundamental parameters of cluster samples are acquired using CMD fitting *** them,the results of 11 OCs are reliable as the observed CMDs are *** propose the crucial role of stellar binarity and confirm the importance of stellar rotation in reproducing eMSTO *** results also show that the impact of age spread is important,as it can adequately explain the structure of young OCs and fit the observed CMDs of intermediate-age OCs better.

关键词： (stars:)binaries:general Galaxy:fundamental parameters (Galaxy:)open clusters and associations:general (stars:)Hertzsprung Russell and C-M-diagrams

BSEC Method for Unveiling Open Clusters and its Application to Gaia DR3:83 New Clusters

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Research in Astronomy and Astrophysics 2024年第5期24卷 169-184页

作者： Zhong-mu Li Cai-Yan Mao Institute of Astronomy and Information Dali UniversityDali 671003China

Open clusters(OCs) are common in the Milky Way, but most of them remain undiscovered. There are numerous techniques, including some machine-learning algorithms, available for the exploration of OCs. However, each method has its limitations and therefore, different approaches to discovering OCs hold significant values. We develop a comprehensive approach method to automatically explore the data space and identify potential OC candidates with relatively reliable membership determination. This approach combines the techniques of Hierarchical Density-Based Spatial Clustering of Applications with Noise, Gaussian mixture model, and a novel cluster member identification technique, color excess constraint. The new method exhibits efficiency in detecting OCs while ensuring precise determination of cluster memberships. Because the main feature of this technique is to add an extra constraint(EC) for the members of cluster candidates using the homogeneity of color excess,compared to typical blind search codes, it is called Blind Search-Extra Constraint(BSEC) method. It is successfully applied to the Gaia Data Release 3, and 83 new OCs are found, whose color–magnitude diagrams(CMDs) are fitted well to the isochrones. In addition, this study reports 621 new OC candidates with discernible main sequence or red giant branch. It is shown that BSEC technique can discard some false negatives of previous works, which takes about three percentage of known clusters. It shows that as an EC, the color excess(or twocolor) constraint is useful for removing fake cluster member stars from the clusters that are identified from the positions and proper motions of stars, and getting more precise CMDs, when differential reddening of member stars of a cluster is not large(e.g., ΔE(G_(BP)-G_(RP)) < 0.5 mag). It makes the CMDs of 15% clusters clearer(in particular for the region near turnoff) and therefore is helpful for CMD and stellar population studies. Our result suggests that the color excess con

关键词： Galaxy stellar content-(Galaxy:)open clusters and associations general-stars fundamental parameters

On convergence of covariance matrix of empirical Bayes hyper-parameter estimator

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Control Theory and Technology 2024年第2期22卷 149-162页

作者： Yue Ju Biqiang mu Tianshi Chen School of Data Science and Shenzhen Research Institute of Big Data The Chinese University of Hong KongShenzhenShenzhen518172GuangdongChina Division of Decision and Control Systems School of Electrical Engineering and Computer ScienceKTH Royal Institute of Technology10044StockholmSweden Key Laboratory of Systems and Control Institute of Systems ScienceAcademy of Mathematics and System ScienceChinese Academy of SciencesBeijing100190China

Regularized system identification has become the research frontier of system identification in the past *** related core subject is to study the convergence properties of various hyper-parameter estimators as the sample size goes to *** this paper,we consider one commonly used hyper-parameter estimator,the empirical Bayes(EB).Its convergence in distribution has been studied,and the explicit expression of the covariance matrix of its limiting distribution has been ***,what we are truly interested in are factors contained in the covariance matrix of the EB hyper-parameter estimator,and then,the convergence of its covariance matrix to that of its limiting distribution is *** general,the convergence in distribution of a sequence of random variables does not necessarily guarantee the convergence of its covariance ***,the derivation of such convergence is a necessary complement to our theoretical analysis about factors that influence the convergence properties of the EB hyper-parameter *** this paper,we consider the regularized finite impulse response(FIR)model estimation with deterministic inputs,and show that the covariance matrix of the EB hyper-parameter estimator converges to that of its limiting ***,we run numerical simulations to demonstrate the efficacy of ourtheoretical results.

关键词： Regularized system identification Hyper-parameter estimator Empirical Bayes Convergence of covariance matrix

Randomized Double-Blind Controlled Clinical Study of Ciprofol and Propofol in Patients with Painless Artificial Abortion

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Journal of Biosciences and Medicines 2024年第8期12卷 154-166页

作者： Xiaoyu Xi Hui Yan Li mu rui Xia Department of the First Affiliated Hospital Yangtze University Jingzhou China

Background and Objectives: Propofol is a commonly used intravenous anesthetic for painless artificial abortion, but the injection pain and related adverse reactions such as those related to respiration and circulation it induces have also been criticized. We aimed to conduct a comparative study on the efficacy, safety and comfort of ciprofol and propofol applied in painless artificial abortion. Materials and Methods: A total of 140 early pregnant patients undergoing painless induced abortion were selected and randomly divided into the ciprofol combined with fentanyl group (Group C) and the propofol combined with fentanyl group (Group P), with 70 cases in each group. The anesthetic effect, depth of anesthesia sedation (NI), onset time, recovery time, recovery time of orientation, retention time in the anesthesia recovery room and total amount of intravenous anesthetic drug were recorded in both groups. The respiratory rate (RR), oxygen saturation (SpO2), mean arterial pressure (MAP), and heart rate (HR) at different time points were recorded. The occurrence of perioperative adverse events, injection pain, postoperative nausea and vomiting, and dizziness were compared. The pain score at 30 minutes after operation and the satisfaction of patients and surgeons with anesthesia were evaluated. Results: The success rate of anesthesia in both groups was 100%. There were no statistically significant differences in the NI value at each time point, intraoperative body movement, recovery time, recovery time of orientation, retention time in the anesthesia recovery room, and total dosage of sedative drugs (ml) between the two groups;the onset time in Group C was longer than that in Group P, with a statistically significant difference (P Conclusion: The efficacy of ciprofol in painless induced abortion is equivalent to that of propofol, and the incidence of adverse reactions is lower than that of propofol, with higher safety and comfort.

关键词： Ciprofol Propofol Fentanyl Artificial Abortion Anesthesia

Neural network based adaptive nonsingular practical predefined-time fault-tolerant control for hypersonic morphing aircraft

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Chinese Journal of Aeronautics 2024年第4期37卷 421-435页

作者： Shihao XU Changzhu WEI Litao ZHANG Rongjun mu School of Astronautics Harbin Institute of TechnologyHarbin 150001China Beijing Institute of Control&Electronics Technology Beijing 100038China

This paper develops a novel Neural Network(NN)-based adaptive nonsingular practical predefined-time controller for the hypersonic morphing aircraft subject to actuator faults. Firstly, a novel Lyapunov criterion of practical predefined-time stability is established. Following the proposed criterion, a tangent function based nonsingular predefined-time sliding manifold and the control strategy are developed. Secondly, the radial basis function NN with a low-complexity adaptation mechanism is incorporated into the controller to tackle the actuator faults and uncertainties. Thirdly, rigorous theoretical proof reveals that the attitude tracking errors can converge to a small region around the origin within a predefined time, while all signals in the closed-loop system remain bounded. Finally, numerical simulation results are presented to verify the effectiveness and improved performance of the proposed control scheme.

关键词： Hypersonic morphing aircraft(HMA) Neural network(NN) Adaptive control Practical predefined-time control Fault-tolerant control

A Lightweight Network with Dual Encoder and Cross Feature Fusion for Cement Pavement Crack Detection

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Computer Modeling in Engineering & Sciences 2024年第7期140卷 255-273页

作者： Zhong Qu Guoqing mu Bin Yuan School of Computer Science and Technology Chongqing University of Posts and TelecommunicationsChongqing400065China School of Software Engineering Chongqing University of Posts and TelecommunicationsChongqing400065China

Automatic crack detection of cement pavement chiefly benefits from the rapid development of deep learning,with convolutional neural networks(CNN)playing an important role in this ***,as the performance of crack detection in cement pavement improves,the depth and width of the network structure are significantly increased,which necessitates more computing power and storage *** limitation hampers the practical implementation of crack detection models on various platforms,particularly portable devices like small mobile *** solve these problems,we propose a dual-encoder-based network architecture that focuses on extracting more comprehensive fracture feature information and combines cross-fusion modules and coordinated attention mechanisms formore efficient feature ***,we use small channel convolution to construct shallow feature extractionmodule(SFEM)to extract low-level feature information of cracks in cement pavement images,in order to obtainmore information about cracks in the shallowfeatures of *** addition,we construct large kernel atrous convolution(LKAC)to enhance crack information,which incorporates coordination attention mechanism for non-crack information filtering,and large kernel atrous convolution with different cores,using different receptive fields to extract more detailed edge and context ***,the three-stage feature map outputs from the shallow feature extraction module is cross-fused with the two-stage feature map outputs from the large kernel atrous convolution module,and the shallow feature and detailed edge feature are fully fused to obtain the final crack prediction *** evaluate our method on three public crack datasets:DeepCrack,CFD,and *** results on theDeepCrack dataset demonstrate the effectiveness of our proposed method compared to state-of-the-art crack detection methods,which achieves Precision(P)87.2%,Recall(R)87.7%,and F-score(F1)87.4%.Thanks to our lightweight cr

关键词： Shallow feature extraction module large kernel atrous convolution dual encoder lightweight network crack detection

Emerging roles and therapeutic potentials of sphingolipids in pathophysiology:emphasis on fatty acyl heterogeneity

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Journal of Genetics and Genomics 2024年第3期51卷 268-278页

作者： Jinming mu Sin Man Lam Guanghou Shui State Key Laboratory of Molecular Developmental Biology Institute of Genetics and Developmental BiologyChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100101China Lipidall Technologies Company Limited ChangzhouJiangsu 213000China

Sphingolipids not only exert structural roles in cellular membranes,but also act as signaling molecules in various physiological and pathological processes.A myriad of studies have shown that abnormal levels of sphingolipids and their metabolic enzymes are associated with a variety of human ***,blood sphingolipids can also be used as biomarkers for disease *** review summarizes the biosynthesis,metabolism,and pathological roles of sphingolipids,with emphasis on the biosynthesis of ceramide,the precursor for the biosynthesis of complex sphingolipids with different fatty acyl *** possibility of using sphingolipids for disease prediction,diagnosis,and treatment is also *** endogenous ceramides and complex sphingolipids along with their specific fatty acyl chain to promote future drug development will also be discussed.

关键词： Sphingolipids Ceramide Therapeutic targets Microdomain Biomarker

Ghost Module Based Residual Mixture of Self-Attention and Convolution for Online Signature Verification

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Computers, Materials & Continua 2024年第4期79卷 695-712页

作者： Fangjun Luan Xuewen mu Shuai Yuan Department of Computer Technology School of Computer Science and EngineeringShenyang Jianzhu UniversityShenyang110168China Liaoning Province Big Data Management and Analysis Laboratory of Urban Construction Shenyang Jianzhu UniversityShenyang110168China Shenyang Branch of National Special Computer Engineering Technology Research Center Shenyang Jianzhu UniversityShenyang110168China

Online Signature Verification (OSV), as a personal identification technology, is widely used in various ***, it faces challenges, such as incomplete feature extraction, low accuracy, and computational heaviness. Toaddress these issues, we propose a novel approach for online signature verification, using a one-dimensionalGhost-ACmix Residual Network (1D-ACGRNet), which is a Ghost-ACmix Residual Network that combines convolutionwith a self-attention mechanism and performs improvement by using Ghost method. The Ghost-ACmix Residualstructure is introduced to leverage both self-attention and convolution mechanisms for capturing global featureinformation and extracting local information, effectively complementing whole and local signature features andmitigating the problem of insufficient feature extraction. Then, the Ghost-based Convolution and Self-Attention(ACG) block is proposed to simplify the common parts between convolution and self-attention using the Ghostmodule and employ feature transformation to obtain intermediate features, thus reducing computational ***, feature selection is performed using the random forestmethod, and the data is dimensionally reducedusing Principal Component Analysis (PCA). Finally, tests are implemented on the MCYT-100 datasets and theSVC-2004 Task2 datasets, and the equal error rates (EERs) for small-sample training using five genuine andforged signatures are 3.07% and 4.17%, respectively. The EERs for training with ten genuine and forged signaturesare 0.91% and 2.12% on the respective datasets. The experimental results illustrate that the proposed approacheffectively enhances the accuracy of online signature verification.

关键词： Online signature verification feature selection ACG block ghost-ACmix residual structure