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Defence Technology（防务技术） 2021年第3期17卷 846-858页

作者： jian-hao Dou xin Jia Zheng-xiang Huang Xiao-hui gu Ying-min Zheng Bin Ma Qiang-qiang Xiao School of Mechanical Engineering Nanjing University of Science and TechnologyNanjing210094JiangsuChina

The use of a shaped liner driven by electromagnetic force is a new means of forming jets. To study the mechanism of jet formation driven by electromagnetic force, we considered the current skin effect and the characteristics of electromagnetic loading and established a coupling model of "ElectriceMagnetic eForce" and the theoretical model of jet formation under electromagnetic force. The jet formation and penetration of conical and trumpet liners have been calculated. Then, a numerical simulation of liner collapse under electromagnetic force, jet generation, and the stretching motion were performed using an ANSYS multiphysics processor. The calculated jet velocity, jet shape, and depth of penetration were consistent with the experimental results, with a relative error of less than 10%. In addition, we calculated the jet formation of different curvature trumpet liners driven by the same loading condition and obtained the influence rule of the curvature of the liner on jet formation. Results show that the theoretical model and the ANSYS multiphysics numerical method can effectively calculate the jet formation of liners driven by electromagnetic force, and in a certain range, the greater the curvature of the liner is, the greater the jet velocity is.

关键词： Electromagnetic field Shaped charge jet formation Theoretical calculation Numerical simulation

Homological Dimensions of Extriangulated Categories and Recollements

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Algebra Colloquium 2023年第4期30卷 667-684页

作者： Weili gu xin Ma Lingling Tan Department of Mathematics Nanjing UniversityNanjing 210093China College of Science Henan University of EngineeringZhengzhou 451191China School of Mathematical Sciences Qufu Normal UniversityQufuShandong 273165China

Let(A,B,C)be a recollement of extriangulated *** this paper we introduce the global dimension and extension dimension of extriangulated categories,and give some upper bounds of global dimensions and extension dimensions of the categories involved in(A,B,C),which give a simultaneous generalization of some results in recollements of abelian categories and triangulated categories.

关键词： extriangulated category recollement global dimension extension dimension

BREAKING THE MONOLITH： STRATEGY, VARIETY, AND PERFORMANCE OF ENTERPRISE INFORMATION SYSTEMS

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Journal of Systems Science and Systems Engineering 2018年第6期27卷 727-770页

作者： Yuanxun gu Lian Qi jian Wang School of Economics and Management Beijing Jiaotong University Beijing 100044 China Rutgers Business School Rutgers the State University of New Jersey Newark 07102 USA School of Managernent Shanghai University Shanghai 200444 China

This paper intends to understand the form of implementations of Enterprise Information Systems （EISs）. EISs are usually provided as packaged software products. Due to the diversities of implementations, EISs are often characterized by their system architectures. A conceptual framework is proposed to delineate the diversity and dynamics of EIS implementations. This framework is constituted of three components, EIS strategy, variety, and process-level performance （SVP）. In particular, the variety of implementations is defined by two constructs, application scope and application depth. A Partial Least Squares structural equation modeling approach is applied to test the hypotheses according to the survey data from 223 project reports of EIS implementations in China. The results show that the EIS strategy and variety can both affect the performance of the implemented EISs. Specifically, application depth has an important mediating effect on the relationship between EIS strategy and performance. EIS strategy and application depth are breakthrough points to improve the performance of the implemented EISs. These findings suggest that the variety plays a central and effective role in the analysis of EIS implementations. This SVP framework highlights the interconnections among its components and captures the form of EIS implementations.

关键词： EIS strategy application scope application depth process-level performance

Age-and Microbiota-Dependent Cell Stemness Plasticity Revealed by Cattle Cell Landscape

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Research 2023年第3期6卷 345-360页

作者： Jia-Jin Wu Senlin Zhu Yi-Fan Tang Fengfei gu Teresa GValencak jian-xin Liu Hui-Zeng Sun Institute of Dairy Science College of Animal SciencesZhejiang UniversityHangzhou 310058China Ministry of Education Key laboratory of Molecular Animal Nutrition Zhejiang UniversityHangzhou 310058China Ministry of Education Innovation Team of Development and Function of Animal Digestive System Zhejiang UniversityHangzhou 310058China

Newborn ruminants are considered functionally monogastric *** poor understanding of cellular differences between newborn and mature ruminants prevents the improvement of health and performance of domestic ***,we performed the single-cell RNA sequencing on the rumen,reticulum,omasum,abomasum,duodenum,jejunum,ileum,cecum,colon,rectum,liver,salivary gland,and mammary gland from newborn and adult cattle.A comprehensive single-cell transcriptomic atlas covering 235,941 high-quality single cells and 78 cell types was deciphered.A Cattle Cell Landscape database(http://***)was established to elaborately display the data and facilitate effective annotation of cattle cell types and subtypes for the broad research *** measuring stemness states of epithelial cells in each tissue type,we revealed that the epithelial cells from newborn forestomach(rumen,reticulum,and omasum)were more transcriptionally indistinct and stochastic compared with the adult stage,which was in contrast to those of abomasum and intestinal *** rapid forestomach development during the early life of calves was driven by epithelial progenitor-like cells with high DNA repair activities and ***,in the forestomach tissues of newborn calves,the Megasphaera genus was involved in regulating the transcriptional plasticity of the epithelial progenitor-like cells by DNA methylation regulation.A novel cell type,the STOML3+cell,was found to be *** apparently plays a crucial role in stemness maintenance of its own and cholangiocytes in the hepatic *** results reveal that the age-and microbiota-dependent cell stemness plasticity drives the postnatal functional maturity of ruminants.

关键词： stomach maturity cattle

Collective Hamiltonian for Multi-O（4） Model

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Communications in Theoretical Physics 2007年第2期47卷 309-316页

作者： gu jian-Zhong Masato Kobayasi China Institute of Atomic Energy P.O. Box 275 （18） Beijing 102413 China Department of Physics Graduate School of Science Kyoto University Kyoto 606-8502 Japan Yukawa Institute for Theoretical Physics Kyoto University Kyoto 606-8502 Japan

The collective Bamiltonian up to the fourth order for multi-O（4） model is derived based on the self-consistent collective-coordinate （SCC） method, which is formulated in the framework of the time-dependent Hartree-Bogoliubov （TDHB） theory. The validity of the collective Hamiltonian is checked in the two special cases of the multi-O（4） model： the case where the number of the shells is equal to one （a single j-shell case）, and the case where the Hartree-Bogoliubov equilibrium point is spherical （the spherical case）. The collective Hamiltonian constitutes a good starting point to study nuclear shape coexistence.

关键词： self-consistent collective-coordinate method multi-O(4) model time-dependent Hartree-Bogoliubov theory collective Hamiltonian

Affinity Adsorption of Bilirubin on Cibacron Blue F3GA-modified Microporous Polytetrafluoroethylene Capillary

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Chemical Research in Chinese Universities 2010年第2期26卷 323-330页

作者： JIN gu YAO jian-xia Department of Chemistry University of Science and Technology of China Hefei 230026 P. R. China

Bilirubin removal from human plasma was obtained via an affinity microporous polytetrafluoroethylene（MPTFE） capillary. The new adsorbent comprised grafted glycidyl methacrylate（GMA） via radiation-induced polymerization as hydrophilic coating and reactive sites; ethylenediamine（EDA） as a spacer arm; Cibacron Blue F3GA（CB F3GA） as an affinity ligand; MPTFE capillary as the supporting matrix. The average density of CB F3GA attachment to MPTFE capillaries was found to be 136.5 μmol/g. The capacity of bilirubin adsorbed on affinity MPTFE capillaries is 76.1 mg bilirubin/g polymer（at 25℃）. This new adsorbent has advantages over both membrane and traditional micro-column, and this system is stable and easy to operate. The results of blood tests suggest the CB F3GA affinity capillary has good blood compatibility.

关键词： Bilirubin removal Radiation grafting Cibacron Blue F3GA Polytetrafluoroethylene Microporous capillary

Dynamical brane creation and annihilation via a background flux

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Science China(Physics,Mechanics & Astronomy) 2022年第2期65卷 24-29页

作者： Yi-Fei Chen jian-xin Lu Interdisciplinary Center for Theoretical Study University of Science and Technology of ChinaPeng Huanwu Center for Fundamental TheoryHefei 230026China

We study the dynamical Myers effect by allowing the fuzzy(or the dynamical dielectric brane)coordinates to be time *** find three novel kinds of the dynamical spherical dielectric branes depending on their respective excess *** first represents a dynamical spherical brane carrying a negative excess energy(having a lower bound)with its radius oscillating periodically between two given non-zero *** second is the one with zero excess energy and whose time dependence can be expressed in terms of a simple *** particular dynamical spherical configuration represents the dielectric brane creation and/or annihilation like a photon in the presence of a background creating an electron-position pair and then annihilating back to a *** third is the one carrying positive excess energy and the radius can also oscillate periodically between two non-zero values but,unlike the first kind,it passes zero twice for each *** of the above can also be interpreted as the time evolution of a semi-spherical D-brane–anti semi-spherical D-brane system.

关键词： dynamical Myers effect D-branes string/M-theory

Damping properties of fly ash/epoxy composites

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Journal of University of Science and Technology Beijing 2008年第4期15卷 509-513页

作者： jian gu Gaohui Wu Xiao Zhao School of Materials Science and Engineering Harbin Institute of Technology Harbin 150001 China

An inexpensive fly ash （FA）, which is from a waste product, was employed to prepare fly ash/epoxy composites. The purpose of this study is to characterize the contributions of matrix viscoelasticity, hollow structure characteristic （porosity）, and filler/matrix interface friction to the high vibration damping capacity of such composites. The damping properties of the composites were investigated in the temperature range of-40 to 150℃ and in the frequency range of 10 to 800 Hz by using a tension-compression mode. The results indicate that the peak value of damping loss factor （tan3） for the fly ash/epoxy composites can reach 0.70-0.90 in test specification, and the attenuation of damping loss factor is inconspicuous with increasing frequency. In addition, scanning electron microscope （SEM） was used to observe the morphology of the fly ash as well as its distribution in the matrix, which will help to analyze the effect of fly ash on the damping properties of the fly ash/epoxy composites.

关键词： composites epoxy fly ash damping property loss factor

The Origin of The Soft X-Ray Excess in the Seyfert 1.5 Galaxy ESO 362-G18

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Research in Astronomy and Astrophysics 2022年第3期22卷 10-32页

作者： Xiao-gu Zhong jian-Cheng Wang Yunnan Observatories Chinese Academy of SciencesKunming 650216China Key Laboratory for the Structure and Evolution of Celestial Objects Chinese Academy of SciencesKunming 650216China University of Chinese Academy of Sciences Beijing 100049China

We review the Seyfert 1.5 Galaxy ESO 362-G18 for exploring the origin of the soft X-ray *** Warm Corona and Relativistic Reflection models are two main scenarios to interpret the soft X-ray excess in active galactic nuclei at *** use the simultaneous X-ray observation data of XMM-Newton and Nu STAR on2016 September 24 to perform spectral analysis in two ***,we analyze the time-average spectra by using Warm Corona and Relativistic Reflection ***,we also explore the Hybrid model,Double Reflection model and Double Warm Corona *** find that both the Warm Corona and Relativistic Reflection models can interpret the time-average spectra well but cannot be distinguished easily based on the time-averaged spectra fit ***,we add the rms and covariance spectra to perform the spectral analysis with time-average *** result shows that the warm corona could reproduce all of these spectra *** hot,optical thin corona and neutral distant reflection will increase their contribution with the temporal frequency,meaning that the corona responsible for X-ray continuum comes from the inner compact X-ray region and the neutral distant reflection is made of some moderate scale neutral clumps.

关键词： galaxies:active galaxies:individual(ESO 362-G18) galaxies:Seyfert

Adversarial data splitting for domain generalization

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Science China(Information Sciences) 2024年第5期67卷 28-42页

作者： Xiang gu jian SUN Zongben XU School of Mathematics and Statistics Xi'an Jiaotong University

Domain generalization aims to learn a model that is generalizable to an unseen target domain,which is a fundamental and challenging task in machine learning for out-of-distribution generalization. This paper proposes a novel domain generalization approach that enforces the learned model to be able to generalize well over the train/val subset splitting of the training dataset. This idea is modeled herein as an adversarial data splitting framework, formulated as a min-max optimization problem inspired by the metalearning approach. The min-max optimization problem is solved by iteratively splitting the training dataset into the training and val subsets to maximize the domain shift measured by the objective function and updating the model parameters to enable the model to generalize well from the training subset to the val subset by minimizing the objective function. This adversarial training approach does not assume the known domain labels of the training data; instead, it automatically investigates the “hard” splitting of the train/val subsets to learn the generalizable model. Extensive experimental results using three benchmark datasets demonstrate the superiority of this approach. In addition, we derive a generalization error bound for the theoretical understanding of our proposed approach.

关键词： domain generalization adversarial learning data splitting meta-learning out of distribution