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International Journal of Mining Science and Technology 2024年第6期34卷 799-819页

作者： Wei Yao Shuai Wang Bangbiao Wu Ying Xu Kaiwen xia State Key Laboratory of Hydraulic Engineering Intelligent Construction and Operation School of Civil EngineeringTianjin UniversityTianjin 300072China China Railway Design Corporation Tianjin 300308China Institute of Geosafety School of Engineering and TechnologyChina University of GeosciencesBeijing 100083China

Understanding the effects of microwave irradiation and thermal treatment on the dynamic compression and fragmentation properties of rocks is essential to quantify energy consumption in rock *** this study,Fangshan granite(FG)specimens were exposed to microwave irradiation and heat *** damage of FG specimens induced by these two methods was compared using X-ray CT scanning and ultrasonic wave *** temperatures of FG after microwave irradiation and thermal treatment were effectively evaluated using a newly proposed technique.A novelty method for precisely determining the geometric features of fragments is developed to estimate the fragmentation ***,the dynamic uniaxial compressive strength(UCS),the dynamic fragmentation characteristics,and the fragmentation energy of FG after these two pretreatment methods can be reasonably *** noticeable distinction of loading rate effect on the dynamic UCS of FG between these two pretreatment methods is first observed.A relationship is established between the dynamic UCS and the damage induced by microwave irradiation and heat ***,fragmentation energy fan analysis is introduced to accurately compare the fragmentation properties of FG after two pretreatment methods in dynamic compression tests.

关键词： Fangshan granite Dynamic experiments Microwave irradiation Thermal treatment Loading rate Fragmentation

Aerodynamic optimization of an adaptive flap for next-generation green aircraft

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Chinese Journal of Aeronautics 2024年第2期37卷 100-122页

作者： Tianlong LIN Rosario PECORA Danilo CILIBERTI Wei xia Shuling HU State Key Laboratory for Strength and Vibration of Mechanical Structures School of Aerospace EngineeringXi’an Jiaotong UniversityXi’an 710049China Deparment of Industrial Engineering Aerospace DivisionUniversity of Naples"FEDERICO II"Napoli 80125Italy

Adaptive,morphing flaps are taking ever-increasing attention in civil aviation thanks to the expected benefits this technology can bring at the aircraft level in terms of high-lift performance improvement and related fuel burnt reduction per *** upon morphing capabilities,it is possible to fix a unique setting for the flap and adapt the flap shape to match the aerodynamic requirements for take-off or *** proper morphed shapes can assure better high-lift performances than those achievable by referring to a conventional ***,standing the unique flap setting for take-off and landing,a dramatic simplification of the flap deployment systems may be *** a consequence of this simplification,the deployment system can be fully hosted in the wing,thus avoiding under-wing nacelles with significantly better aerodynamics and fuel *** first step for a rational design of an adaptive flap consists in defining the target morphed shapes and the unique optimal flap setting in the take-off and landing *** this work,aerodynamic optimization analyses are carried out to determine the best flap setting and related morphed shapes in compliance with the take-off and landing requirements of a reference civil transport *** different initial conditions are adopted to avoid the optimization falling into local optima,thus obtaining four groups of optimal candidate *** comparing each candidate’s performance through 2D and 3D simulations,the optimal configuration has been selected.2D simulations show that the optimal configuration is characterized by a maximum lift increase of 31.92%in take-off and 9.04%in *** to 3D simulations,the rise in maximum lift equals 22.26%in take-off and 3.50%in *** results are finally verified through wind tunnel tests,and the aerodynamic mechanism behind the obtained improvements is explained by carefully analyzing the flow field around the flap.

关键词： Morphing wings High-lift system Adaptive flap Computational Fluid Dynamics(CFD) Wind tunnel tests

High-Order Two-Scale Asymptotic Paradigm for the Elastodynamic Homogenization of Periodic Composites

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Acta Mechanica Solida Sinica 2024年第1期37卷 124-138页

作者： Wei-Zhi Luo Mu He Liang xia Qi-Chang He State Key Laboratory of Intelligent Manufacturing Equipment and Technology Huazhong University of Science and TechnologyWuhan 430074China Laboratoire Modélisation et Simulation Multi-Echelle MSME UMR 8208 CNRSUniversite Gustave Eiffel77454 Marne-la-ValléeFrance

The classical two-scale asymptotic paradigm provides macroscopic and microscopic analyses for the elastodynamic homogenization of periodic composites based on the spatial or/and temporal variable,which offers an approximate framework for the asymptotic homogenization analysis of the motion ***,in this framework,the growing complexity of the homogenization formulation gradually becomes an obstacle as the asymptotic order *** such a context,a compact,fast,and accurate asymptotic paradigm is *** work reviews the high-order spatial two-scale asymptotic paradigm with the effective displacement field representation and optimizes the implementation by symmetrizing the tensor to be ***,the modified implementation gets rid of the excessive memory consumption required for computing the high-order tensor,which is demonstrated by representative one-and two-dimensional *** numerical results show that(1)the contrast of the material parameters between media in composites directly affects the convergence rate of the asymptotic results for the homogenization of periodic composites,(2)the convergence error of the asymptotic results mainly comes from the truncation error of the modified asymptotic homogenized motion equation,and(3)the excessive norm of the normalized wavenumber vector in the two-dimensional inclusion case may lead to a non-convergence of the asymptotic results.

关键词： Composites Homogenization Asymptotic analysis Dynamics Dispersion

An Adaptive Local Grid Nesting-based Genetic Algorithm for Multi-earth Observation Satellites' Area Target Observation

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Journal of Systems Science and Systems Engineering 2024年第2期33卷 232-258页

作者： Ligang Xing Wei xia xiaoxuan Hu Waiming Zhu Yi Wu School of Management Hefei University of TechnologyHefei 230009China Key Laboratory of Process Optimization and Inteligent Decision-making Ministry of EducationHefei 230009China Intelligent Interconnected Systems Laboratory of Anhui Province Hefei 230009China

The Scheduling of the Multi-EOSs Area Target Observation(SMEATO)is an EOS resource schedul-ing problem highly coupled with computational *** advances in EOS technology and the ex-pansion of wide-area remote sensing applications have increased the practical significance of *** this paper,an adaptive local grid nesting-based genetic algorithm(ALGN-GA)is proposed for developing SMEATO ***,a local grid nesting(LGN)strategy is designed to discretize the target area into parts,so as to avoid the explosive growth of calculations.A genetic algorithm(GA)framework is then used to share reserve information for the population during iterative evolution,which can generate high-quality solutions with low computational *** this basis,an adaptive technique is introduced to determine whether a local region requires nesting and whether the grid scale is *** effectiveness of the proposed model is assessed experimentally with nine randomly generated tests at different *** results show that the ALGN-GA offers advantages over several conventional algorithms in 88.9%of instances,especially in large-scale *** fully demonstrate the high efficiency and stability of the ALGN-GA.

关键词： Multi-EOSs scheduling area target observation adaptive genetic algorithm local grid nesting

Data-driven Anomaly Detection Method Based on Similarities of Multiple Wind Turbines

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Journal of Modern Power Systems and Clean Energy 2024年第3期12卷 803-818页

作者： xiangjun Zeng Ming Yang Chen Feng Mingqiang Wang Lingqin xia the College of Electrical Engineering&New Energy China Three Gorges UniversityYichang 443002China the Key Laboratory of Power System Intelligent Dispatch and Control Shandong UniversityJinan 250061China

The operating conditions of wind turbines(WTs)in the same wind farm(WF)may share similarities due to their shared manufacturing process,control strategy,and operating ***,the similarities of WTs are seldom considered in WT anomaly detection,resulting in the disregard of useful *** paper proposes a method to improve the reliability and accuracy of WT anomaly detection using the supervisory control and data acquisition(SCADA)data of multiple WTs in the same ***,a similarity assessment method based on a comparison of different observation time series is proposed,which objectively quantifies the similarities of WT operating ***,the SCADA data of the target WT and selected WTs that are similar are used to establish several estimation models through a long short-term memory(LSTM)*** models that exhibit good estimation performance are used to construct a combined estimation model that estimates the variations in the monitored variables of the target ***,an anomaly detection method that jointly compares the effective value and information entropy of the residuals is proposed to identify *** effectiveness and accuracy of the proposed method are verified using the data of two actual WFs.

关键词： Anomaly detection information entropy long short-term memory similarity assessment wind farm wind turbines

Chain Extender-induced Hydrogen Bonding Organization Determines the Morphology and Properties of Thermoplastic Polycarbonate Polyurethane

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Chinese Journal of Polymer Science 2024年第1期42卷 87-96,I0009页

作者： Yi-Lang Qin Ping Zhu Chen-Xi Ouyang xia Dong Fuwai Hospital Chinese Academyof Medical Sciences&Peking Union Medical College/National Center for Cardiovascular DiseasesBejing 100037China CASKey Laboratoryof Engineering Plastics CAS Research/Education Centerfor Excellence in Molecular SciencesInstitute ofChemistryChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

Thermoplastic polycarbonate polyurethanes(PCUs) are multiblock copolymers that have been applied for medical devices for long time. Aliphatic diols are common chain extenders(CE) involved in the composition of the hard segments of PCU. However, limited knowledge was discovered about how the chemical structure of CE affects the hydrogen bonding organization within PCUs and their mechanical *** investigate this problem, a group of PCUs were synthesized respectively by extending the polymer chain with 1,4-butanediol(BDO),aminoethanol(MEA), ethanediol(EO) as three kinds of chain extenders. Tiny differences in the CE chemical structure results in remarkable variations in phase separation, condensed morphologies, thermal and mechanical properties, which are characterized by Fourier transform infrared spectrometer, atomic force microscopy, small-angle X-ray scattering, differential scanning calorimetry, and tensile tests. The microstructural evolution during unilateral deformation and the different mechanism induced by the different CEs was probed and unveil by in situ wide-and small-angle X-ray diffraction. Symmetry of CE can improve the organization of the hydrogen bonding. The coherence strength of the urethane/urea group also plays a key role by comparing the two PCUs with ethanediol and aminoethanol.

关键词： Thermoplastic polycarbonate polyurethane Chain extender Hydrogen bonding Mechanical properties

A novel graph oversampling framework for node classification in class-imbalanced graphs

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Science China(Information Sciences) 2024年第6期67卷 214-229页

作者： Riting xia Chunxu ZHANG Yan ZHANG Xueyan LIU Bo YANG Key Laboratory of Symbolic Computation and Knowledge Engineering of Ministry of Education Jilin University College of Artificial Intelligence Jilin University College of Computer Science and Technology Jilin University College of Communication Engineering Jilin University

Graph neural network(GNN) is a promising method to analyze graphs. Most existing GNNs adopt the class-balanced assumption, which cannot deal with class-imbalanced graphs well. The oversampling technique is effective in alleviating class-imbalanced problems. However, most graph oversampling methods generate synthetic minority nodes and their edges after applying GNNs. They ignore the problem that the representations of the original and synthetic minority nodes are dominated by majority nodes caused by aggregating neighbor information through GNN before oversampling. In this paper, we propose a novel graph oversampling framework, termed distribution alignment-based oversampling for node classification in classimbalanced graphs(named Graph-DAO). Our framework generates synthetic minority nodes before GNN to avoid the dominance of majority nodes caused by message passing in GNNs. Additionally, we introduce a distribution alignment method based on the sum-product network to learn more information about minority nodes. To our best knowledge, it is the first to use the sum-product network to solve the class-imbalanced problem in node classification. A large number of experiments on four real datasets show that our method achieves the optimal results on the node classification task for class-imbalanced graphs.

关键词： graph neural network class-imbalanced graphs sum-product network oversampling node classification

Tilapia Head Glycolipid Alleviates Indomethacin-Induced Gastric Ulcer via Regulating Oxidative Stress and Inflammation Through COX/PGE2 Signaling Pathway in Adult Rats

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Journal of Ocean University of China 2024年第3期23卷 743-754页

作者： WANG Bohui WU Haixing SHAO Mingyang JIANG Mengqi SU Ruiheng GAO xia xia Guanghua SHI Haohao SHEN Xuanri Hainan Engineering Research Center of Aquatic Resources Efficient Utilization in South China Sea College of Food Science and TechnologyHainan UniversityHaikou 570228China Collaborative Innovation Center of Marine Food Deep Processing Dalian Polytechnic UniversityDalian 116000China College of Food and Engineering Hainan Tropical Ocean UniversitySanya 572022China

The aim of this experiment was to investigate the ameliorative effect and molecular mechanism of tilapia head glycolipid(TH-GL)on indomethacin(IDM)-induced gastric ulcer in male Sprague Dawley(SD)*** gastric ulcer model was established by oral administration of 30mgkg^(-1) IDM after 7 days of TH-GL or omeprazole(OME)administration in *** the macroscopic gastric injury symptoms,gastric mucosa protective factor cyclooxygenase 1(COX-1),cyclooxygenase 2(COX-2),prostaglandin E_(2)(PGE_(2)),the levels of oxidative stress,and inflammatory cytokine expression levels in the rats were *** experimental results showed that multiple ulcers appeared on the gastric surface of the rats in the model *** to the model group,TH-GL significantly alleviated gastric ulcers and reduced the gastric damage index in *** addition,TH-GL significantly promoted the expression of constitutive enzyme COX-1 while inhibited the expression of inducible enzyme COX-2,and make PGE2 maintain at normal ***-GL also inhibited oxidative stress and inflammatory responses,increased superoxide dismutase(SOD)activity and glutathione(GSH)content,decreased the level of malondialdehyde(MDA)and the content of pro-inflammatory *** conclusion,these results suggested that TH-GL could maintain the expression levels of COX-1 and PGE2 while inhibit the expression of COX-2 in the gastric of rat and then prevent IDM-induced gastric ulcer,which may be related to the regulation of oxidative stress and inflammatory ***,TH-GL might be a new option for the prevention of gastric diseases induced by IDM.

关键词： tilapia head glycolipid indomethacin gastric ulcer oxidative stress inflammation

Physical and numerical investigations of target stratum selection for ground hydraulic fracturing of multiple hard roofs

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International Journal of Mining Science and Technology 2024年第5期34卷 699-712页

作者： Binwei xia Yanmin Zhou Xingguo Zhang Lei Zhou Zikun Ma State Key Laboratory of Coal Mine Disaster Dynamics and Control Chongqing UniversityChongqing 400044China School of Resources and Safety Engineering Chongqing UniversityChongqing 400044China

Ground hydraulic fracturing plays a crucial role in controlling the far-field hard roof,making it imperative to identify the most suitable target stratum for effective *** experiments are conducted based on engineering properties to simulate the gradual collapse of the roof during longwall top coal caving(LTCC).A numerical model is established using the material point method(MPM)and the strain-softening damage constitutive model according to the structure of the physical *** simulations are conducted to analyze the LTCC process under different hard roofs for ground hydraulic *** results show that ground hydraulic fracturing releases the energy and stress of the target stratum,resulting in a substantial lag in the fracturing of the overburden before collapse occurs in the hydraulic fracturing *** hydraulic fracturing of a low hard roof reduces the lag effect of hydraulic fractures,dissipates the energy consumed by the fracture of the hard roof,and reduces the abutment ***,it is advisable to prioritize the selection of the lower hard roof as the target stratum.

关键词： Target stratum selection Ground hydraulic fracturing Hard roof control Fracture network Material point method

Engineering W/O/W pickering emulsion for the enhanced antigen delivery and immune responses

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Particuology 2024年第9期92卷 224-233页

作者： Sihua Wu xiaonan Huang Yin Ma Naoki Asakawa Yufei xia State Key Laboratory of Biochemical Engineering Institute of Process EngineeringChinese Academy of SciencesBeijing100081China Key Laboratory of Biopharmaceutical Preparation and Delivery Chinese Academy of SciencesBeijing100190China Division of Molecular Science Graduate School of Science and TechnologyGunma University1-5-1Tenjin-choKiryu376-8515Japan Sinovac Biotech Ltd. Beijing100085China School of Chemical Engineering Nanjing Tech UniversityNanjing211816China School of Chemical Engineering University of Chinese Academy of SciencesBeijing100049China

Tumor immunotherapy,particularly cancer vaccines,holds promise for combating cancer by harnessing tailored immune responses against malignant ***,conventional approaches face challenges in efficiently delivering antigens for optimal immune *** adjuvants,like MF59,enhance cellular uptake but struggle to induce robust CD8^(+)T cell ***,we introduce a novel strategy employing a water-in-oil-in-water(W/O/W)multiple Pickering emulsion(mPE)for antigen *** mPE,utilizing biocompatible,pH-sensitive particles,encapsulates antigens within the inner water phase,ensuring enhanced intracellular processing and dictating the intracellular fate of antigens for improved *** vitro and in vivo studies demonstrated that mPEs induced robust dendritic cells activation and antigen cross-presentation,leading to a significantly enhanced immune ***,calcium phosphate-stabilized mPE(CaP-mPE)illustrated the more robust IFN-γ^(+)T cell *** comparison with traditional surfactant-stabilized multiple emulsions,CaP-mPE significantly inhibit tumor growth and effectively prolong the survival of tumor-bearing *** innovative approach offers a promising avenue for the development of effective cancer vaccines with potent cellular immune responses.

关键词： Cancer vaccine Multiple pickeringemulsion Adjuvant Antigen delivery Anti-tumor response