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A UNIFORM CONVeRGeNT PeTROV-GALeRKIN MeTHOD FOR A CLASS OF TURNING POINT PROBLeMS

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Journal of Computational Mathematics 2024年第5期42卷 1356-1379页

作者： Li feng Zhongyi huang Department of Mathematical Sciences Tsinghua UniversityBeijing 100084China

In this paper,we propose a numerical method for turning point problems in one dimension based on Petrov-Galerkin finite element method(PGFeM).We first give a priori estimate for the turning point problem with a single boundary turning *** we use PGFeM to solve it,where test functions are the solutions to piecewise approximate dual *** prove that our method has a first-order convergence rate in both L∞h norm and a discrete energy norm when we select the exact solutions to dual problems as test *** results show that our scheme is efficient for turning point problems with different types of singularities,and the convergency coincides with our theoretical results.

关键词： Turning point problem Petrov-Galerkin finite element method Uniform convergency

Sequence [2,3]-Sigmatropic Rearrangement: One-Pot Synthesis of Proparggyl Allenylamines

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Chinese Journal of Chemistry 2024年第18期42卷 2223-2227页

作者： Huihui feng Yujuan Xie Lliang huang Yongqing Xu Junhai huang huangdi feng College of Chemistry and Chemical engineering Shanghai University of Engineering ScienceShanghai 201620China Shanghai Frontiers Science Research Centerfor Druggability of Cardiovascular noncoding RNA Institute for Frontier Medical Technology Shanghai Universityof Engineering ScienceShanghai 201620China

Allenes,served as highly sought-after building blocks,are an indispensable component of synthetic *** utility in modulating the chemical,physical,and pharmaceutical properties of organic compounds make allenes a desirable choice in various ***,we report a facile method for the atom-economical synthesis of propargyl allenylamines via an underdeveloped[2,3]-sigmatropic *** strategy employs easily accessible propargylamines as starting materials,which are first converted into propargyl ammonium salts,followed by a base-promoted[2,3]-sigmatropic *** one-pot,two-step reaction proceeds in the absence of transition metals,displays a very broad scope,and does not require the introduction of the electron-withdrawing group into the starting materials.

关键词： Allene Propargylamine C-N activation Sigmatropic rearrangement Metal-free Synthetic methods Domino reactions

A possible relationship between serum sex hormones and benign prostatic hyperplasia/Iower urinary tract symptoms in men who underwent transurethral prostate resection

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Asian Journal of Andrology 2017年第2期19卷 230-233页

作者： Yu Wu Hong Pan Wei-Ming Wang Ding Xu Liang Zhang Zheng-Qin Gu Qiang Bai un Qi e-feng huang Department of Urology Xinhua Hospital School of Medicine Shanghai Jiao Tong University Shanghai 200092 China Department of Gynecology Xinhua Hospital School of Medicine Shanghai Jiao Tong University Shanghai 200092 China Department of Assisted Reproduction Medicine International Peace Maternity and Child Health Hospital School of Medicine Shanghai Jiao Tong University Shanghai 200030 China

In this study, we examined the relationship between sex hormone levels and lower urinary tract symptoms （LUTS） in men with benign prostatic hyperplasia （BPH） who underwent transurethral surgery. The study was conducted in 158 patients who came to our hospital for surgery. Clinical conditions were assessed by body mass index （BMI）, digital rectal examination, International Prostate Symptom Score （IPSS） and transrectal ultrasound （TRUS）. The levels of sex hormones （including total testosterone （TT）, estradiol （e2）, progesterone （P）, luteinizing hormone （LH）, follicle-stimulating hormone （FSH） and prolactin （PRL）） and prostate-specific antigen （PSA） were reviewed. Correlations were determined through statistical analysis. The mean age was 72.06 _＋ 8.68 years. The total IPSS was significantly associated with the TT level （r = -0.21, P = 0.01）. Other sex hormone levels were not correlated with total IPSS. However, some ratios such as e2/TT （r = 0.23, P = 0o00） and FSH/LH （r = -0.17, P = 0.04） were associated with total IPSS. Further analysis showed that the nocturia was associated with age （r = 0.16, P = 0.04）, BMI （r = 0.21, P = 0.01）, and TT （r = -0.19, P = 0.02）. Moreover, we divided the patients into two subgroups based on IPSS severity （〈20 or 〉20）. The mean TT level was in the normal range, but it was significantly related to the presence of severe LUTS. In summary, our study has shown that the severity of LUTS is associated with TT, eJTT and FSH/LH in men who underwent prostate surgery. Increasing nocturia was observed in lower testosterone patients. Additional larger studies are needed to elucidate the potential mechanisms.

关键词： aging benign prostatic hyperplasia lower urinary tract symptoms sex hormones testosterone

A Deep Model for Partial Multi-label Image Classification with Curriculum-based Disambiguation

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Machine Intelligence Research 2024年第4期21卷 801-814页

作者： feng Sun Ming-Kun Xie Sheng-Jun huang MIIT Key Laboratory of Pattern Analysis and Machine Intelligence College of Computer Science and TechnologyNanjing University of AeronauticsandAstronauticsNanjing211106China

In this paper,we study the partial multi-label(PML)image classification problem,where each image is annotated with a candidate label set consisting of multiple relevant labels and other noisy *** PML methods typically design a disambiguation strategy to filter out noisy labels by utilizing prior knowledge with extra assumptions,which unfortunately is unavailable in many real ***,because the objective function for disambiguation is usually elaborately designed on the whole training set,it can hardly be optimized in a deep model with stochastic gradient descent(SGD)on *** this paper,for the first time,we propose a deep model for PML to enhance the representation and discrimination *** the one hand,we propose a novel curriculum-based disambiguation strategy to progressively identify ground-truth labels by incorporating the varied difficulties of different *** the other hand,consistency regularization is introduced for model training to balance fitting identified easy labels and exploiting potential relevant *** experimental results on the commonly used benchmark datasets show that the proposed method significantlyoutperforms the SOTA methods.

关键词： Partial multi-label image classification curriculum-based disambiguation consistency regularization label difficulty candidatelabel set.

Strong Limit Theorems for Weighted Sums under the Sub-linear expectations

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Acta Mathematicae Applicatae Sinica 2024年第3期40卷 862-874页

作者： feng-xiang feng Ding-cheng WANG Qun-ying WU Hai-wu huang School of Mathematics and Statistics Guilin University of TechnologyGuilin 541004China School of Mathematical Science University of Electronic Science and Technology of ChinaChengdu 611731China School of Science Guilin University of Aerospace TechnologyGuilin 541004China

In this article,we study strong limit theorems for weighted sums of extended negatively dependent random variables under the sub-linear *** establish general strong law and complete convergence theorems for weighted sums of extended negatively dependent random variables under the sub-linear *** results of strong limit theorems are more general than some related results previously obtained by Thrum(1987),Li et al.(1995)and Wu(2010)in classical probability space.

关键词： sub-linear expectation complete convergence complete moment convergence the maximal weighted sums

Adaptive event-Triggered Time-Varying Output Group Formation Containment Control of Heterogeneous Multiagent Systems

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Ieee/CAA Journal of Automatica Sinica 2024年第6期11卷 1398-1409页

作者： Lihong feng Bonan huang Jiayue Sun Qiuye Sun Xiangpeng Xie College of Information Science and engineering Northeastern UniversityShenyang 110819China College of Automation and College of Artificial Intelligence Nanjing University of Posts and TelecommunicationsNanjing 210023China Ieee

In this paper,a class of time-varying output group formation containment control problem of general linear hetero-geneous multiagent systems(MASs)is investigated under directed *** MAS is composed of a number of tracking leaders,formation leaders and followers,where two different types of leaders are used to provide reference trajectories for movement and to achieve certain formations,***,compen-sators are designed whose states are estimations of tracking lead-ers,based on which,a controller is developed for each formation leader to accomplish the expected ***,two event-triggered compensators are proposed for each follower to evalu-ate the state and formation information of the formation leaders in the same group,***,a control protocol is designed for each follower,utilizing the output information,to guide the output towards the convex hull generated by the forma-tion leaders within the ***,the triggering sequence in this paper is decomposed into two sequences,and the inter-event intervals of these two triggering conditions are provided to rule out the Zeno ***,a numerical simulation is intro-duced to confirm the validity of the proposed results.

关键词： Adaptive control event-triggered mechanisms for-mation containment(FC) heterogeneous multiagent systems time-varying group formation.

Starlet:Network defense resource allocation with multi-armed bandits for cloud-edge crowd sensing in IoT

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Digital Communications and Networks 2024年第3期10卷 586-596页

作者： Hui Xia Ning huang Xuecai feng Rui Zhang Chao Liu College of Computer Science and Technology Ocean University of ChinaQingdao266100China

The cloud platform has limited defense resources to fully protect the edge servers used to process crowd sensing data in Internet of *** guarantee the network's overall security,we present a network defense resource allocation with multi-armed bandits to maximize the network's overall ***,we propose the method for dynamic setting of node defense resource thresholds to obtain the defender(attacker)benefit function of edge servers(nodes)and ***,we design a defense resource sharing mechanism for neighboring nodes to obtain the defense capability of ***,we use the decomposability and Lipschitz conti-nuity of the defender's total expected utility to reduce the difference between the utility's discrete and continuous arms and analyze the difference ***,experimental results show that the method maximizes the defender's total expected utility and reduces the difference between the discrete and continuous arms of the utility.

关键词： Internet of things Defense resource sharing Multi-armed bandits Defense resource allocation

Interaction Mechanisms between Natural Debris Flow and Rigid Barrier Deflectors:A New Perspective for Rational Design and Optimal Arrangement

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Computer Modeling in engineering & Sciences 2024年第5期139卷 1679-1699页

作者： Yu huang Beilei Liu Dianlei feng Hao Shi Department of Geotechnical engineering College of Civil EngineeringTongji UniversityShanghai200092China Department of Hydraulic engineering College of Civil EngineeringTongji UniversityShanghai200092China

Rigid barrier deflectors can effectively prevent overspilling landslides,and can satisfy disaster prevention ***,the mechanisms of interaction between natural granular flow and rigid barrier deflectors require further *** date,few studies have investigated the impact of deflectors on controlling viscous debris flows for geological disaster *** investigate the effect of rigid barrier deflectors on impact mechanisms,a numerical model using the smoothed particle hydrodynamics(SPH)method with the Herschel–Bulkley model is proposed to simulate the interaction between natural viscous flow and single/dual barriers with and without *** model was validated using laboratory flume test data from the ***,the model was used to investigate the influence of the deflector angle and multi-barrier *** optimal configuration of multi-barriers was analyzed with consideration to the barrier height and distance between the barriers,because these metrics have a significant impact on the viscous flow pile-up,run-up,and overflow *** investigation considered the energy dissipation process,retention efficiency,and dead-zone *** with bare barriers with similar geometric characteristics and spatial distribution,rigid barriers with deflectors exhibit superior effectiveness in preventing the overflow and overspilling of viscous debris *** for the rational design of deflectors and the optimal arrangement of multi-barriers are provided to mitigate geological disasters.

关键词： Rigid barrier deflectors deflector angle single-barrier dual-barrier arrangements viscous debris flow over-spilling delta-plus-SPH

exceptional points enhance sensing in silicon micromechanical resonators

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Microsystems & Nanoengineering 2024年第1期10卷 17-25页

作者： Man-Na Zhang Lei Dong Li-feng Wang Qing-An huang Key Laboratory of MeMS of the Ministry of education Southeast UniversityNanjing 210096China

exceptional points(ePs)have recently emerged as a new method for engineering the response of open physical systems,that is,systems that interact with the *** systems at the ePs exhibit a strong response to a small ***,we show a method by which the sensitivity of silicon resonant sensors can be enhanced when operated at *** our experiments,we use a pair of mechanically coupled silicon micromechanical resonators constituting a parity-time(PT)-symmetric *** perturbations introduced on the mechanically coupled spring cause the frequency to split from the ePs into the PT-symmetric regime without broadening the two spectrum linewidths,and this frequency splitting scales with the square root of the perturbation *** overall signal-tonoise ratio is still greatly enhanced,although the measured noise spectral density of the eP sensing scheme has a slight increase comparable to the traditional *** results pave the way for resonant sensors with ultrahigh sensitivity.

关键词： resonant symmetric points