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Defence Technology（防务技术） 2024年第1期31卷 27-40页

作者： Rui liu Danfeng Yang Kunyu xiong Ying-Lei Wang Qi-Long Yan Science and Technology on Combustion Internal Flow and Thermo-structure LaboratoryNorthwestern Polytechnical UniversityXi'an710072China Xi'an Modern Chemistry Research Institute Xi'an710065China

Boron has high mass and volume calorific values,but it is difficult to ignite and has low combustion *** literature review summarizes the strategies that are used to solve the above-mentioned problems,which include coatings of boron by using fluoride compounds,energetic composites,metal fuels,and metal *** techniques include recrystallization,dual-solvent,phase transfer,electrospinning,*** one of the effective coating agents,the fluorine compounds can react with the oxide shell of boron *** comparison,the energetic composites can effectively improve the flame temperature of boron powder and enhance the evaporation efficiency of oxide film as a condensed *** and metal oxides would react with boron powder to form metal borides with a lower ignition point,which could reduce its ignition temperature.

关键词： Boron powder coating Structure and morphology Condensed phase thermal reaction Ignition and combustion

Influence of powder oxidation on powder properties and formability in H13 hot-work steels processed by electron beam melting

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Journal of Iron and Steel Research International 2024年第4期31卷 924-932页

作者： Wei liu Yan Wang Li-xiong Han Ying-kang Wei Hui-ping Tang Shi-feng liu School of Metallurgical Engineering Xi'an University of Architecture and TechnologyXi'an 710055ShaanxiChina School of Engineering Zhejiang University City CollegeHangzhou 310015ZhejiangChina

The oxygen content of metal powder is decisive for the recyclability of *** research on the effect of oxygen content on powder properties and material formability has practical significance for economical production with additive manufacturing while preventing the waste of ***,we deliberately oxidized the powder by baking at high temperature to increase the oxygen content in the powder and gave the calculation method of the oxygen content in the powder oxidation *** majority of oxygen element was found in the oxide particles in the powder and the oxide flm on the powder surface,which did affect the flowability of the *** is worth noting that the increase in the oxygen content does not change the phase of H13 steel,but it can promote the molten pool flow and obtain a smoother *** increase in the oxygen content in the powder is not the decisive factor for the formability and defects of the printed *** is the combined effect of the powder deformation,the increase in the oxygen content,and the impurity pollution after repeated use,which leads to the limitation of repeated utilization of the powder.

关键词： Additive manufacturing Electron beam melting H13 steel powder-Powder oxidation

Digital Transformation and the Frontier of China's State Governance

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Social Sciences in China 2024年第2期45卷 70-91页

作者： xiong Yihan liu Zhenlin Sschool of International Relations and Public Affairs Fudan University

Digital transformation has emerged as a significant area of interest for scholars in global political science and public *** advancement of digital technologies is driving a comprehensive transformation across the economy,society,and governance,thereby profoundly affecting the state governance of *** introduction of new technologies has altered traditional power dynamics,leading to centralization and empowerment-the power redistribution issue of the digital era,which is a fundamental concern in China's state *** effects of technological power,including empowerment and disempowerment of various entities,give rise to or reinforce four secondary issues:the problem of data silos and collaborative governance in internal government operations,the challenges related to technological deficits and platform regulation in market regulation,the issues of the digital divide and social justice in social governance,and concerns about privacy,transparency,and rights *** paper integrates specific cases from China's digital transformation and digital government initiatives to examine these cuttingedge issues and to analyze the impact of digital government reforms implemented by local Chinese governments on traditional government theories.

关键词： digital governance digital transformation state governance

Identifying malicious traffic under concept drift based on intraclass consistency enhanced variational autoencoder

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Science China(Information Sciences) 2024年第8期67卷 238-252页

作者： Xiang LUO Chang liu Gaopeng GOU Gang xiong Zhen LI Binxing FANG Institute of Information Engineering Chinese Academy of Sciences School of Cyber Security University of Chinese Academy of Sciences School of Computer Science and Technology Harbin Institute of Technology (Shenzhen)

Accurate identification of malicious traffic is crucial for implementing effective defense countermeasures and has led to extensive research efforts. However, the continuously evolving techniques employed by adversaries have introduced the issues of concept drift, which significantly affects the performance of existing methods. To tackle this challenge, some researchers have focused on improving the separability of malicious traffic representation and designing drift detectors to reduce the number of false ***, these methods often overlook the importance of enhancing the generalization and intraclass consistency in the representation. Additionally, the detectors are not sufficiently sensitive to the variations among different malicious traffic classes, which results in poor performance and limited robustness. In this paper, we propose intraclass consistency enhanced variational autoencoder with Class-Perception detector(ICE-CP) to identify malicious traffic under concept drift. It comprises two key modules during training:intraclass consistency enhanced(ICE) representation learning and Class-Perception(CP) detector construction. In the first module, we employ a variational autoencoder(VAE) in conjunction with Kullback-Leibler(KL)-divergence and cross-entropy loss to model the distribution of each input malicious traffic flow. This approach simultaneously enhances the generalization, interclass consistency, and intraclass differences in the learned representation. Consequently, we obtain a compact representation and a trained classifier for nondrifting malicious traffic. In the second module, we design the CP detector, which generates a centroid and threshold for each malicious traffic class separately based on the learned representation, depicting the boundaries between drifting and non-drifting malicious traffic. During testing, we utilize the trained classifier to predict malicious traffic classes for the testing samples. Then, we use the CP det

关键词： concept drift cyberspace security intrusion detection malicious traffic identification variational autoencoder

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Engineering of geometrical configurations in dual-atom catalysts for electrocatalytic applications

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Journal of Energy Chemistry 2024年第7期94卷 273-287页

作者： Tao Zhang Yifan liu Liang Xue Jingwen Sun Pan xiong Junwu Zhu Key Laboratory for Soft Chemistry and Functional Materials of Ministry Education School of Chemistry and Chemical EngineeringNanjing University of Science and TechnologyNanjing210094JiangsuChina

Geometrical configurations play a crucial role in dual-atom catalysts(DACs)for electrocatalytic *** progress has been made to design DACs electrocatalysts with various geometri-cal configurations,but in-depth understanding the relationship between geometrical configurations and metal-metal interaction mechanisms for designing targeted DACs is still *** this review,the recent progress in engineering of geometrical configurations of DACs is systematically *** on the polarity of geometrical configuration,DACs can be classified into two different types that are homonuclear and heteronuclear ***,with regard to the geometrical configurations of the active sites,homonuclear DACs are identified into adjacent and bridged configurations,and heteronuclear DACs can be classified into adjacent,bridged,and separated ***,metal-metal interactions in DACs with different geometrical configurations are ***,the applications of DACs in different electrocatalytic reactions are discussed,including the oxygen reduction reaction(ORR),oxygen evolution reaction(OER),hydrogen evolution reaction(HER),and other ***,the future challenges and perspectives for advancements in DACs are *** review aims to provide inspiration for the design of highly effcient DACs towards energy relatedapplications.

关键词： Dual-atom catalysts Geometrical configurations Homonuclear Heteronuclear Electrocatalysis

d-d Orbital coupling induced by crystal-phase engineering assists acetonitrile electroreduction to ethylamine

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Journal of Energy Chemistry 2024年第2期89卷 216-225,I0006页

作者： Honggang Huang Yao Chen Hui Fu cun Chen Hanjun Li Zhe Zhang Feili Lai Shuxing Bai Nan Zhang Tianxi liu Key Laboratory of Synthetic and Biological Colloids Ministry of EducationSchool of Chemical and Material EngineeringJiangnan UniversityWuxi 214122JiangsuChina Department of Chemistry KU LeuvenCelestijnenlaan 200FLeuven 3001Belgium College of Chemistry and Chemical Engineering Qingdao UniversityQingdao 266071ShandongChina

The d-d orbital coupling induced by crystal-phase engineering can effectively adjust the electronic structure of electrocatalysts,thus showing significant catalytic performance,while it has been rarely explored in electrochemical acetonitrile reduction reaction(ARR)to ***,we successfully realize the structural transformation of Pd Cu metallic aerogels(MAs)from face-centered cubic(FCC)to body-centered cubic(BCC)through annealing ***,the BCC Pd Cu MAs exhibit excellent ARR performance with high ethylamine selectivity of 90.91%,Faradaic efficiency of 88.60%,yield rate of 316.0 mmol h^(-1)g^(-1)_(Pd+Cu)and long-term stability for consecutive electrolysis within 20 h at-0.55 V *** hydrogen electrode,outperforming than those of FCC Pd Cu *** the membrane electrode assembly system,BCC Pd Cu MAs also demonstrate excellent ethylamine yield rate of 389.5 mmol h^(-1)g^(-1)_(Pd+Cu).Density functional theory calculation reveals that the d-d orbital coupling in BCC Pd Cu MAs results in an evident correlation effect for the interaction of Pd and Cu sites,which boosts up the Cu sites electronic activities to enhance ARR *** work opens a new route to develop efficient ARR electrocatalysts from the perspective of crystalline structure transformation.

关键词： d-d Orbital coupling Crystal-phase engineering Metallic aerogels Acetonitrile electroreduction reaction Ethylamine

An Updated Lagrangian Particle Hydrodynamics (ULPH)-NOSBPD Coupling Approach forModeling Fluid-Structure Interaction Problem

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Computer Modeling in Engineering & Sciences 2024年第10期141卷 491-523页

作者： Zhen Wang Junsong xiong Shaofan Li Xin Lai Xiang liu Lisheng liu Hubei Key Laboratory of Theory and Application of Advanced Materials Mechanics Wuhan University of TechnologyWuhan430070China Department of Civil and Environmental Engineering The University of CaliforniaBerkeleyCA 94720USA Department of Engineering Structure and Mechanics Wuhan University of TechnologyWuhan430070China

A fluid-structure interaction approach is proposed in this paper based onNon-Ordinary State-Based Peridynamics(NOSB-PD)and Updated Lagrangian Particle Hydrodynamics(ULPH)to simulate the fluid-structure interaction problem with large geometric deformation and material failure and solve the fluid-structure interaction problem of Newtonian *** the coupled framework,the NOSB-PD theory describes the deformation and fracture of the solid material *** is applied to describe the flow of Newtonian fluids due to its advantages in computational *** framework utilizes the advantages of NOSB-PD theory for solving discontinuous problems and ULPH theory for solving fluid problems,with good computational stability and robustness.A fluidstructure coupling algorithm using pressure as the transmission medium is established to deal with the fluidstructure *** dynamic model of solid structure and the PD-ULPH fluid-structure interaction model involving large deformation are verified by numerical *** results agree with the analytical solution,the available experimental data,and other numerical ***,the accuracy and effectiveness of the proposed method in solving the fluid-structure interaction problem are *** fluid-structure interactionmodel based on ULPH and NOSB-PD established in this paper provides a new idea for the numerical solution of fluidstructure interaction and a promising approach for engineering design and experimental prediction.

关键词： Fluid-structure interaction(FSI) updated lagrangian particle hydrodynamics peridynamics meshfree method

Interaction between systemic iron parameters and left ventricular structure and function in the preserved ejection fraction population:a two-sample bidirectional Mendelian randomization study

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Journal of Geriatric Cardiology 2024年第1期21卷 64-80页

作者： xiong-Bin MA Yong-Ming liu Yan-Lin LV Lin QIAN The First Clinical Medical College of Lanzhou University LanzhouGansuChina Geriatric Cardiovascular Department and Gansu Clinical Research Center for Geriatric Diseases First Hospital of Lanzhou UniversityGansuChina

BACKGROUND Left ventricular(LV)remodeling and diastolic function in people with heart failure(HF)are correlated with iron status;however,the causality is *** Mendelian randomization(MR)study investigated the bidirectional causal relationship between systemic iron parameters and LV structure and function in a preserved ejection fraction *** Transferrin saturation(TSAT),total iron binding capacity(TIBC),and serum iron and ferritin levels were extracted as instrumental variables for iron parameters from meta-analyses of public genome-wide association *** without myocardial infarction history,HF,or LV ejection fraction(LVEF)<50%(n=16,923)in the UK Biobank Cardiovascular Magnetic Resonance Imaging Study constituted the outcome *** dataset included LV end-diastolic volume,LV endsystolic volume,LV mass(LVM),and LVM-to-end-diastolic volume ratio(LVMVR).We used a two-sample bidirectional MR study with inverse variance weighting(IVW)as the primary analysis method and estimation methods using different algorithms to improve the robustness of the *** In the IVW analysis,one standard deviation(SD)increased in TSAT significantly correlated with decreased LVMVR(β=-0.1365;95%confidence interval[CI]:-0.2092 to-0.0638;P=0.0002)after Bonferroni ***,no significant relationships were observed between other iron and LV *** Bonferroni correction,reverse MR analysis showed that one SD increase in LVEF significantly correlated with decreased TSAT(β=-0.0699;95%CI:-0.1087 to-0.0311;P=0.0004).No heterogeneity or pleiotropic effects evidence was observed in the *** We demonstrated a causal relationship between TSAT and LV remodeling and function in a preserved ejection fraction population.

关键词： fraction function parameters

Deep learning for drug-drug interaction prediction:A comprehensive review

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Quantitative Biology 2024年第1期12卷 30-52页

作者： Xinyue Li Zhankun xiong Wen Zhang Shichao liu College of Informatics Huazhong Agricultural UniversityWuhanChina

The prediction of drug-drug interactions(DDIs)is a crucial task for drug safety research,and identifying potential DDIs helps us to explore the mechanism behind combinatorial *** wet chemical experiments for DDI are cumbersome and time-consuming,and are too small in scale,limiting the efficiency of DDI ***,it is particularly crucial to develop improved computational methods for detecting drug *** the development of deep learning,several computational models based on deep learning have been proposed for DDI *** this review,we summarized the high-quality DDI prediction methods based on deep learning in recent years,and divided them into four categories:neural network-based methods,graph neural network-based methods,knowledge graph-based methods,and multimodal-based ***,we discuss the challenges of existing methods and future potential *** review reveals that deep learning can significantly improve DDI prediction performance compared to traditional machine *** learning models can scale to large-scale datasets and accept multiple data types as input,thus making DDI predictions more efficient and accurate.

关键词： deep learning drug-drug interactions graph neural network knowledge graph multimodal deep learning neural network

Intelligent fault diagnosis methods toward gas turbine: A review

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Chinese Journal of Aeronautics 2024年第4期37卷 93-120页

作者： Xiaofeng liu Yingjie CHEN liuqi xiong Jianhua WANG Chenshuang LUO Liming ZHANG Kehuan WANG School of Transportation Science and Engineering Beihang UniversityBeijing 100191China Systems Engineering Research Institute China State Shipbuilding CorporationBeijing 100094China

Fault diagnosis plays a significant role in conducting condition-based maintenance and health management for gas turbines(GTs) to improve reliability and reduce costs. Various diagnosis methods developed by modeling engine systems or certain components implement faults detection and diagnosis based on the measurement of systemic parameters deviations. However, these conventional model-based methods are hindered by limitations of inability to handle the nonlinear nature, measurement uncertainty, fault coupling and other implementing problems. Recently, the development of artificial intelligence algorithms has provided an effective solution to the above problems, triggering broad researches for data-driven fault diagnosis methods with better accuracy,dynamic performance, and universality. This paper presents a systematic review of recently proposed intelligent fault diagnosis methods for GT engines, according to the classification of shallow learning methods, deep learning methods and hybrid intelligent methods. Moreover, the principle of typical algorithms, the evolution of enhanced methods, and the assessment of pros and cons are summarized to conclude the present status and look forward to the future in the field of GT fault diagnosis. Possible directions for development in method validation, information fusion, and interpretability of intelligent diagnosis methods are concluded in the end to provide insightful concepts for scholars in related fields.

关键词： Fault diagnosis Health management Gas turbine Artificial intelligence Intelligent diagnosis method