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An Upper Bound for the w-Weak Global Dimension of Pullbacks

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Algebra Colloquium 2021年第4期28卷 689-700页

作者： jin Xie Gaohua tang College of Mathematical Sciences Sichuan Normal University Chengdu 610068China College of Sciences Beibu Gulf UniversityQinzhouGuangxi 535011China

Let R be a commutative ring with identity and I0 an ideal of *** introduce and study the c-weak global dimension ***(R/I0)of the factor ring R/*** T be a w-linked extension of R,and we also introduce the wR-weak global dimension ***(T)of *** show that the ring T with ***(T)=0 is exactly a field and the ring T with ***(T)≤1 is exactly a *** an application,we give an upper bound for the w-weak global dimension of a Cartesian square(RDTF,M).More precisely,if T is w-linked over R,then ***(R)≤max{***(T)+w-fdR T,***(D)+w-fdn D}.Furthermore,for a Milnor square(RDTF,M),we obtain ***(R)≤max{***(T)+w-fdR T,***(D)+w-fdR D}.

关键词： c-operation c-flat module c-flat dimension wR-flat module WR-flat dimension

Histone Deacetylase Inhibitor SAHA Induces Expression of Fatty Acid-Binding Protein 4 and Inhibits Replication of Human Cytomegalovirus

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Virologica Sinica 2021年第6期36卷 1352-1362页

作者： Zhongshun Liu Baoqin xuan Shubing tang Zhikang Qian CAS Key Laboratory of Molecular Virology and Immunology Institute Pasteur of ShanghaiChinese Academy of SciencesUniversity of the Chinese Academy of SciencesShanghai 200031China University of Chinese Academy of Sciences Beijing 100049China

Suberoylanilide hydroxamic acid(SAHA) is a histone deacetylase inhibitor that shows marked efficacy against many types of cancers and is approved to treat severe metastatic cutaneous T-cell lymphomas. In addition to its anticancer activity,SAHA has significant effects on the growth of many viruses. The effect of SAHA on replication of human cytomegalovirus(HCMV) has not, however, been investigated. Here, we showed that the replication of HCMV was significantly suppressed by treatment with SAHA at concentrations that did not show appreciable cytotoxicity. SAHA reduced transcription and protein levels of HCMV immediate early genes, showing that SAHA acts at an early stage in the viral life-cycle. RNAsequencing data mining showed that numerous pathways and molecules were affected by SAHA. Interferon-mediated immunity was one of the most relevant pathways in the RNA-sequencing data, and we confirmed that SAHA inhibits HCMV-induced IFN-mediated immune responses using quantitative Real-time PCR(qRT-PCR). Fatty acid-binding protein 4(FABP4), which plays a role in lipid metabolism, was identified by RNA-sequencing. We found that FABP4 expression was reduced by HCMV infection but increased by treatment with SAHA. We then showed that knockdown of FABP4 partially rescued the effect of SAHA on HCMV replication. Our data suggest that FABP4 contributes to the inhibitory effect of SAHA on HCMV replication.

关键词： Histone deacetylases inhibitor(HDACI) Suberoylanilide hydroxamic acid(SAHA) Human cytomegalovirus(HCMV) Fatty acid-binding protein 4(FABP4)

Joint inversion of gravity and vertical gradient data based on modified structural similarity index for the structural and petrophysical consistency constraint

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Geodesy and Geodynamics 2023年第5期14卷 485-499页

作者： Sheng Liu Xiangyun Wan Shuanggen jin Bin Jia Quan Lou Songbai xuan Binbin Qin Yiju tang Dali Sun Henan University of Urban Construction Pingdingshan 467041China Institute of Geophysics China Earthquake AdministrationBeijing 100080China School of Surveying and Land Information Engineering Henan Polytechnic UniversityJiaozuo 454000China Shanghai Astronomical Observatory Chinese Academy of SciencesShanghai 200030China The First Monitoring and Application Center CEATianjin 300180China

Joint inversion is one of the most effective methods for reducing non-uniqueness for geophysical *** current joint inversion methods can be divided into the structural consistency constraint and petrophysical consistency constraint methods,which are mutually ***,there is a need for joint inversion methods that can comprehensively consider the structural consistency constraints and petrophysical consistency *** paper develops the structural similarity index(SSIM)as a new structural and petrophysical consistency constraint for the joint inversion of gravity and vertical gradient *** SSIM constraint is in the form of a fraction,which may have analytical ***,converting the fractional form to the subtractive form can solve the problem of analytic singularity and finally form a modified structural consistency index of the joint inversion,which enhances the stability of the SSIM constraint applied to the joint *** to the reconstructed results from the cross-gradient inversion,the proposed method presents good performance and *** SSIM algorithm is a new joint inversion method for petrophysical and structural *** can promote the consistency of the recovered models from the distribution and the structure of the physical property ***,applications to synthetic data illustrate that the algorithm proposed in this paper can well process the synthetic data and acquire good reconstructed results.

关键词： Joint inversion Gravity and vertical gradient data Modified structural similarity index

A Study of the Stability Properties in Simulation of Wave Propagation with SPH Method

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China Ocean Engineering 2017年第2期31卷 173-181页

作者： CHANG Jiang LIU Shu-xue LI jin-xuan State Key Laboratory of Coastal and Offshore Engineering Dalian University of Technology

When ordinary Smoothed Particle Hydrodynamics （SPH） method is used to simulate wave propagation in a wave tank, it is usually observed that the wave height decays and the wave length elongates along the direction of wave propagation. Accompanied with this phenomenon, the pressure under water decays either and shows a big oscillation simultaneously. The reason is the natural potential tensile instability of modeling water motion with ordinary SPH which is caused by particle negative stress in the computation. I＇o deal with the problems, a new sextic kernel function is proposed to reduce this instability. An appropriate smooth length is given and its computation criterion is also suggested. At the same time, a new kind dynamic boundary condition is introduced. Based on these improvements, the new SPH method named stability improved SPH （SISPH） can simulate the wave propagation well. Both the water surface and pressure can be well expressed and the oscillation of pressure is nearly eliminated. Compared with other improved methods, SISPH can truly reveal the physical reality without bringing some new problems in a simple way.

关键词： wave propagation SPH method instability sextic kernel function SISPH

Rts: learning robustly from time series data with noisy label

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Frontiers of Computer Science 2024年第6期18卷 186332-186332页

作者： ZHOU Zhi jin Yi-xuan Li Yu-Feng National Key Laboratory for Novel Software Technology Nanjing University

Significant progress has been made in machine learning with large amounts of clean labels and static data. However, in many real-world applications, the data often changes with time and it is difficult to obtain massive clean annotations, that is, noisy labels and time series are faced simultaneously. For example, in product-buyer evaluation, each sample records the daily time behavior of users, but the long transaction period brings difficulties to analysis, and salespeople often erroneously annotate the user’s purchase behavior. Such a novel setting, to our best knowledge, has not been thoroughly studied yet, and there is still a lack of effective machine learning methods. In this paper, we present a systematic approach RTS both theoretically and empirically, consisting of two components, Noise-Tolerant Time Series Representation and Purified Oversampling Learning. Specifically, we propose reducing label noise’s destructive impact to obtain robust feature representations and potential clean samples. Then, a novel learning method based on the purified data and time series oversampling is adopted to train an unbiased model. Theoretical analysis proves that our proposal can improve the quality of the noisy data set. Empirical experiments on diverse tasks, such as the house-buyer evaluation task from real-world applications and various benchmark tasks, clearly demonstrate that our new algorithm robustly outperforms many competitive methods.

关键词： weakly-supervised learning time-series classification class-imbalanced learning

Improvements in properties of NdFeB magnets obtained via magnetron sputtering and thermal diffusion

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Journal of Rare Earths 2024年第9期42卷 1710-1716,I0003页

作者： jin tang Weichao Huang Dan Li School of Electronic Engineering Guangxi University of Science and TechnologyLiuzhou545006China China Rare Earth(Guangxi)jinyuan Rare Earth New Materials Co. Ltd.Hezhou542603China China Rare Earth Group Co. Ltd.Ganzhou341000China Center of Experimental Teaching for Common Courses Panzhihua UniversityPanzhihua617000China

The grain boundary diffusion process(GBDP) of Dy and DyAl on sintered NdFeB magnets was conducted via magnetron-sputtering deposition of Dy and DyAl films to enhance coercivity(H_(cj)),The magnetic properties,microstructure and anti-corrosion properties of Dy-surface-alloying NdFeB magnets obtained via magnetron sputtering and thermal diffusion were *** H_(cj) of the Dy_(95)Al_(5)-NdFeB magnet increases by 32.68%,while the remanence declines ***,X-ray diffraction and microstructural analysis confirm the formation of Dy-rich shells,the higher-magnetic-anisotropy field of hard(Nd_(x)Dy_(1-x))2(FeAl)_(14)B magnetic phases and an optimised grain boundary structu re,contributing to the H_(cj)enhancement of the *** elemental distribution and diffusion mechanism of the magnets are also ***,the corrosion resistance of the Dy_(95)Al_(5)-NdFeB magnet is substantially improved by enhancing the electrochemical stability and optimising the distribution and morphology of the intergranular *** findings of this study are of substantial importance in the development of low-heavy rare-earth sintered NdFeB magnets.

关键词： Magnetron sputtering NdFeB Rare earths Microstructure Magnetic property Corrosion resistance

Effects of Coal Rank and High Organic Sulfur on the Structure and Optical Properties of Coal-based Graphene Quantum Dots

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Acta Geologica Sinica(English Edition) 2018年第3期92卷 1218-1230页

作者： tang Yuegang HUAN xuan LAN Chunyuan XU Miaoxin College of geoscience and Surveying Engineering China University of Mining & Technology (Beijing) Beijing 100083 China

Coal-based graphene quantum dots(GQDs) were successfully produced via a one-step chemical synthesis from six different coal ranks, from which two superhigh organic sulfur(SHOS) coals were selected as natural S-doped carbon sources for the preparation of S-doped GQDs. The effects of coal properties on coal-based GQDs were analyzed by means of high-resolution transmission electron microscopy(HRTEM), X-ray diffraction(XRD), Fourier transform infrared(FTIR) spectroscopy, X-ray photoelectron spectroscopy(XPS), ultraviolet-visible(UV-Vis) absorption spectroscopy, and fluorescence emission spectra. It was shown that all coal samples can be used to prepare GQDs, which emit bluegreen and blue fluorescence under ultraviolet light. Anthracite-based GQDs have a hexagonal crystal structure without defects, the largest size, and densely arranged carbon rings in their lamellae; the highrank bituminous coal-based GQDs are relatively reduced in size, with their hexagonal crystal structure being only faintly visible; the low-rank bituminous coal-based GQDs are the smallest, with sparse lattice fringes and visible internal defects. As the metamorphism of raw coals increases, the yield decreases and the fluorescence quantum yield(QY) initially increases and then decreases. Additionally, the surface of GQDs that were prepared using high-rank SHOS coal(high-rank bituminous coal) preserves rich sulfur content even after strong oxidation, which effectively adjusts the bandgap and improves the fluorescence QY. Thus, high-rank bituminous coal with SHOS content can be used as a natural S-doped carbon source to prepare S-doped GQDs, extending the clean utilization of low-grade coal.

关键词： coal graphene quantum dots coal rank organic sulfur China

Advanced Transmission Electron Microscopy for Identification of Atomic-Scale Configurations of Zeolite-Supported Metal Catalysts

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Chinese Journal of Chemistry 2022年第19期40卷 2371-2373页

作者： xuan tang Jiajie Ye Yun Guo Sheng Dai Key Laboratory for Advanced Materials and Feringa Nobel Prize Scientist Joint Research Center Frontiers Science Center for Materiobiology and Dynamic ChemistryEast China University of Science and TechnologyShanghai200237 China Key Laboratory for Advanced Materials Research Institute of Industrial CatalysisSchool of Chemistry and Molecular EngineeringEast China University of Science and Technology130 Meilong RoadShanghai200237 China

Zeolite-supported metal catalysts have important applications in various catalytic reactions,but unveiling their atomic-scale structures is always a grand *** developed transmission electron microscopy(TEM)characterization techniques,e.g.,integrated differential-phase contrast(iDPC)scanning transmission electron microscopy(STEM)is emerging as a powerful tool for visualizing the electron beam-sensitive materials at atomic resolution,thus,providing new opportunities for imaging the exact configurations of metal species in the various channels of *** emerging topic summarizes recent progress utilizing iDPC-STEM-related technique for determination of the structures of metal species in zeolites that should offer insights into the structure-property relationships of zeolite-supported metal catalysts.A brief perspective about the new TEM technique is also presented,showing prospects in this field that will stimulate further scientific research in zeolite-supported metal catalysts.

关键词： Metal-zeolite Catalyst structure Heterogeneous catalysis TEM characterization Electron microscopy

Numerical study of hydrodynamic mechanism of dynamic tidal power

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Water Science and Engineering 2018年第3期11卷 220-228页

作者： Peng Dai Ji-sheng Zhang jin-hai Zheng Kees Hulsbergen Gijs van Banning Jeroen Adema Zi-xuan tang State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Hohai UniversityNanjing 210098China State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Nanjing Hydraulic Research InstituteNanjing 210029China College of Harbor Coastal and Offshore Engineering Hohai UniversityNanjing 210098China Hulsbergen Hydraulic Innovation&Design H2iD Dieren6953 CRThe Netherlands ARCADIS Nederland BV Zwolle8017 JSThe Netherlands

Dynamic tidal power is a new way of capturing tidal energy by building a water head using a dike perpendicular to the coast. This study explored the hydrodynamic mechanism of the water head across an intended dynamic tidal power dike system using the Delft3 D-FLOW software module. The propagating wave was simulated in a rectangular domain with a horizontal sea bottom at a 30-m depth. A significant water head was created across the dike by blocking the water. The water head increased with increasing dike length and increasing undisturbed tidal current acceleration. The maximum water head for the dike with a length of 50 km, located 900 km from the western boundary, was 2.15 m,which exceeded the undisturbed tidal range. The time series of the water head behaved in a manner identical to the undisturbed tidal current acceleration. The distribution of the water head over the dike assumed an elliptical shape. A parasitic wave was generated at the attachment and scattered outward. The phase lag across the dike did not behave as a linear function of the detour distance.

关键词： Dynamic tidal power Marine renewable energy Added mass Phase-shift Coastal engineering Delft3D