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Estimation of unfrozen water content of saturated sandstones using nuclear magnetic resonance, mercury intrusion porosimetry, and ultrasonic tests

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第9期16卷 3465-3484页

作者： Fei Liu Shibing huang Gang Liu Shilin yu School of Resources and Environmental Engineering Wuhan University of Science and TechnologyWuhan430081China Hubei Key Laboratory for Efficient Utilization and Agglomeration of Metallurgic Mineral Resources Wuhan University of Science and TechnologyWuhan430081China

The unfrozenwater content(UWC)is a crucial parameter that affects the strength and thermal properties of rocks in relation to engineering construction and geological disasters in cold *** this study,three different methods were employed to test and estimate the UWC of saturated sandstones,including nuclear magnetic resonance(NMR),mercury intrusion porosimetry(MIP),and ultrasonic *** NMR method enabled the direct measurement of the UWC of sandstones using the free induction decay(FID).The MIP method was used to analyze the pore structures of sandstones,with the UWC subsequently calculated based on pore ice ***,the MIP test constituted an indirect measurement ***,a correlation was established between the P-wave velocity and the UWC of these sandstones based on the mixture theory,which could be employed to estimate the UWC as an empirical *** methods demonstrated that the UWC initially exhibited a rapid decrease from 0C to5C and then generally became constant beyond20***,these test methods had different *** NMR method was used to directly and accurately calculate the UWC in the ***,the cost and complexity of NMR equipment have precluded its use in the *** UWC can be effectively estimated by the MIP test,but the estimation accuracy is influenced by the ice crystallization process and the pore size *** P-wave velocity has been demonstrated to be a straightforward and practical empirical parameter and was utilized to estimate the UWC based on the mixture *** method may be more suitable in the *** methods confirmed the existence of a hysteresis phenomenon in the freezing-thawing *** average hysteresis coefficient was approximately 0.538,thus validating the GibbseThomson *** study not only presents alternative methodologies for estimating the UWC of saturated sandstones but also contribute to our understanding of the freezin

关键词： Unfrozen water content(UWC) Nuclear magnetic resonance(NMR) Mercury intrusion porosimetry(MIP) Pore structures P-wave velocity Sandstone

Attention Guided Multi Scale Feature Fusion Network for Automatic Prostate Segmentation

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Computers, Materials & Continua 2024年第2期78卷 1649-1668页

作者： yuchun Li Mengxing huang yu Zhang Zhiming Bai School of Information and Communication Engineering Hainan UniversityHaikouChina College of Computer Science and Technology Hainan UniversityHaikouChina Urology Department Haikou Municipal People’s Hospital and Central South University Xiangya Medical College Affiliated HospitalHaikouChina School of Information Science and Technology Hainan Normal UniversityHaikouChina

The precise and automatic segmentation of prostate magnetic resonance imaging(MRI)images is vital for assisting doctors in diagnosing prostate *** recent years,many advanced methods have been applied to prostate segmentation,but due to the variability caused by prostate diseases,automatic segmentation of the prostate presents significant *** this paper,we propose an attention-guided multi-scale feature fusion network(AGMSF-Net)to segment prostate MRI *** propose an attention mechanism for extracting multi-scale features,and introduce a 3D transformer module to enhance global feature representation by adding it during the transition phase from encoder to *** the decoder stage,a feature fusion module is proposed to obtain global context *** evaluate our model on MRI images of the prostate acquired from a local *** relative volume difference(RVD)and dice similarity coefficient(DSC)between the results of automatic prostate segmentation and ground truth were 1.21%and 93.68%,*** quantitatively evaluate prostate volume on MRI,which is of significant clinical significance,we propose a unique *** essential performance evaluation and validation experiments have demonstrated the effectiveness of our method in automatic prostate segmentation.

关键词： Prostate segmentation multi-scale attention 3D Transformer feature fusion MRI

Semantic-aware entity alignment for low resource language knowledge graph

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Frontiers of Computer Science 2024年第4期18卷 97-106页

作者： Junfei TANG Ran SONG yuxin huang Shengxiang GAO Zhengtao yu Faculty of Information Engineering and Automation Kunming University of Science and TechnologyKunming 650500China yunnan Key Laboratory of Artificial Intelligence Kunming University of Science and TechnologyKunming 650500China

Entity alignment(EA)is an important technique aiming to find the same real entity between two different source knowledge graphs(KGs).Current methods typically learn the embedding of entities for EA from the structure of KGs for *** EA models are designed for rich-resource languages,requiring sufficient resources such as a parallel corpus and pre-trained language ***,low-resource language KGs have received less attention,and current models demonstrate poor performance on those low-resource ***,researchers have fused relation information and attributes for entity representations to enhance the entity alignment performance,but the relation semantics are often *** address these issues,we propose a novel Semantic-aware Graph Neural Network(SGNN)for entity ***,we generate pseudo sentences according to the relation triples and produce representations using pre-trained ***,our approach explores semantic information from the connected relations by a graph neural *** model captures expanded feature information from *** results using three low-resource languages demonstrate that our proposed SGNN approach out performs better than state-of-the-art alignment methods on three proposed datasets and three public datasets.

关键词： graph neural network knowledge graph entity alignment low-resource language

Electron engineering of nickel phosphide for Ni^(δ+) in electrochemical nitrate reduction to ammonia

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Nano Research 2024年第6期17卷 4864-4871页

作者： Jie Hu Hao huang Miao yu Shuang Wang Jinping Li College of Environmental Science and Engineering Taiyuan University of TechnologyJinzhong 030600China School of Sustainable Energy Materials and Science Jinhua Advanced Research InstituteJinhua 321000China Shanxi Key Laboratory of Gas Energy Efficient and Clean Utilization Taiyuan University of TechnologyTaiyuan 030024China

The electrochemical reduction of nitrate to ammonia(ENRA)provides an efficient approach to remove nitrate pollution and achieve ammonia production ***,inspired by bio-enzyme in denitrifying bacteria,a carbon-coated nickel phosphide(NiPC)nanosheet derived from metal-organic frameworks(MOFs)is proposed as an efficient catalyst for *** electron engineering,controllable Ni^(δ+)in nickel phosphide is achieved by regulating the degree of phosphating,which enhances its activity for the hydrogenation of *** the result,Niδ+becomes one of dominating factors determining the efficiency of the ENRA reaction in nickel *** optimal NiPC catalyst exhibits impressive property toward ENRA:NH_(4)^(+)Faraday efficiency of 96.68%,NH4+selectivity of 99.04%,and nitrate conversion rate of 90.43%under low nitrate concentration(200 mg·L^(−1)).This work opens a new avenue for the design of next-generation catalysts through electron engineering for ENRA.

关键词： electron engineering transition metal phosphide nitrate reduction ammonia production metal-organic frameworks

Systematic Elastostatic Stiffness Model of Over-Constrained Parallel Manipulators Without Additional Constraint Equations

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Chinese Journal of Mechanical Engineering 2024年第4期37卷 258-276页

作者： Chao Yang Wenyong yu Wei Ye Qiaohong Chen Fengli huang College of Mechanical and Electrical Engineering Jiaxing UniversityJiaxing 314001ZhejiangChina Zhejiang Siekon Transmission Technology Co. Ltd.Jiaxing 314001ZhejiangChina National and Local Joint Engineering Research Center of Reliability Analysis and Testing for Mechanical and Electrical Products Zhejiang Sci-Tech UniversityHangzhou 310018ZhejiangChina School of Computer Science and Technology Zhejiang Sci-Tech UniversityHangzhou 310018ZhejiangChina

The establishment of an elastostatic stiffness model for over constrained parallel manipulators(PMs),particularly those with over constrained subclosed loops,poses a challenge while ensuring numerical *** study addresses this issue by proposing a systematic elastostatic stiffness model based on matrix structural analysis(MSA)and independent displacement coordinates(IDCs)extraction *** begin,the closed-loop PM is transformed into an open-loop PM by eliminating constraints.A subassembly element is then introduced,which considers the flexibility of both rods and *** approach helps circumvent the numerical instability typically encountered with traditional constraint *** IDCs and analytical constraint equations of nodes constrained by various joints are summarized in the appendix,utilizing multipoint constraint theory and singularity analysis,all unified within a single coordinate ***,the open-loop mechanism is efficiently closed by referencing the constraint equations presented in the appendix,alongside its elastostatic *** proposed method proves to be both modeling and computationally efficient due to the comprehensive summary of the constraint equations in the Appendix,eliminating the need for additional *** example utilizing an over constrained subclosed loops demonstrate the application of the proposed *** conclusion,the model proposed in this study enriches the theory of elastostatic stiffness modeling of PMs and provides an effective solution for stiffness modeling challenges they present.

关键词： Parallel manipulator Elastostatic stiffness model Matrix structural analysis Subassembly element Independent displacement coordinates

Multiscale spatiotemporal meteorological drought prediction:A deep learning approach

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Advances in Climate Change Research 2024年第2期15卷 211-221页

作者： Jia-Li ZHANG Xiao-Meng huang yu-Ze SUN Department of Earth System Science Ministry of Education Key Laboratory for Earth System ModellingInstitute for Global Change StudiesTsinghua UniversityBeijing 100084China

Reliable monitoring and thorough spatiotemporal prediction of meteorological drought are crucial for early warning and decision-making regarding drought-related *** utilisation of multiscale methods is effective for a comprehensive evaluation of drought occurrence and progression,given the complex nature of meteorological ***,the nonlinear spatiotemporal features of meteorological droughts,influenced by various climatological,physical and environmental factors,pose significant challenges to integrated prediction that considers multiple indicators and time *** address these constraints,we introduce an innovative deep learning framework based on the shifted window transformer,designed for executing spatiotemporal prediction of meteorological drought across multiple *** formulate four prediction indicators using the standardized precipitation index and the standard precipitation evaporation index as core methods for drought definition using the ERA5 reanalysis *** indicators span time scales of approximately 30 d and one ***-term indicators capture more anomalous variations,whereas long-term indicators attain comparatively higher accuracy in predicting future *** focus on the East Asian region,notable for its diverse climate conditions and intricate terrains,to validate the model's efficacy in addressing the complexities of nonlinear spatiotemporal *** model's performance is evaluated from diverse spatiotemporal viewpoints,and practical application values are analysed by representative drought *** results substantiate the effectiveness of our proposed model in providing accurate multiscale predictions and capturing the spatiotemporal evolution characteristics of *** of the four drought indicators accurately delineates specific facets of the meteorological drought ***,three representative drought events,namely flash drought,sustained drought and severe drought,

关键词： Meteorological drought Spatiotemporal prediction Multiscale Swim transformer Deep learning

Elevational and temporal patterns of pollination success in distylous and homostylous buckwheats(Fagopyrum)in the Hengduan Mountains

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Plant Diversity 2024年第5期46卷 661-670页

作者： Ling-yun Wu Shuang-Quan huang Ze-yu Tong Faculty of Resources and Environmental Science Hubei UniversityWuhan 430062China Institute of Evolution and Ecology School of Life SciencesCentral China Normal UniversityWuhan 430079China

Reproductive strategies of sexually dimorphic plants vary in response to the ***,we ask whether the sexual systems of Fagopyrum species(i.e.,selfing homostylous and out-crossing distylous)represent distinct adaptive strategies to increase reproductive success in changing alpine *** answer this question,we determined how spatial and temporal factors(e.g.,elevation and peak flowering time)affect reproductive success(i.e.,stigmatic pollen load)in nine wild Fagopyrum species(seven distylous and two homostylous)among 28 populations along an elevation gradient of 1299-3315 m in the Hengduan Mountains,southwestern *** also observed pollinators and conducted hundreds of hand pollinations to investigate inter/intra-morph compatibility,self-compatibility and pollen limitation in four Fagopyrum species(two distylous and two homostylous).We found that Fagopyrum species at higher elevation generally had bigger flowers and more stigmatic pollen loads;lateflowering individuals had smaller flowers and lower pollen *** pollen deposition was more variable in distylous species than in homostylous *** seed set was not pollenlimited in all species,we found that fruit set was much lower in distylous species,which rely on frequent pollinator visits,than in homostylous species capable of autonomous *** findings that pollination success increases at high elevations and decreases during the flowering season suggest that distylous and homostylous species have spatially and temporally distinct reproductive strategies related to environment-dependent pollinator activity.

关键词： Biodiversity hotspot Elevation gradient Fagopyrum Stigmatic pollen load Temporal pattern

Escape probability for isotropic emitters near Kerr black hole with astrometric

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Communications in Theoretical Physics 2024年第5期76卷 128-133页

作者： yu-Xuan Han Qing-Hua Zhu Qing-Guo huang CAS Key Laboratory of Theoretical Physics Institute of Theoretical PhysicsChinese Academy of SciencesBeijing 100190China School of Physical Sciences University of Chinese Academy of SciencesNo.19A Yuquan RoadBeijing 100049China Department of Physics Chongqing UniversityChongqing 401331China School of Fundamental Physics and Mathematical Sciences Hangzhou Institute for Advanced Study UCASHangzhou 310024China

The paper investigates the escape probability for isotropic emitters near a Kerr black *** propose a new approach to obtain the escape probability in a general manner,going beyond previous case-by-case *** approach is based on studies of the black hole shadow with astrometric observable and can be applied to emitters with an arbitrary 4-velocities and locations,even to the emitters outside of the equatorial *** also consider representative examples illustrating how escape probabilities vary with distance,velocity,and inclination ***,this new approach provides an effective method for studying escape probabilities near Kerr black holes.

关键词： Kerr black hole photon escape probability isotropic emitters

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Bone Research 2024年第1期12卷 122-136页

作者： Nan-yu Zou Ran Liu Mei huang yu-Rui Jiao Jie Wei Yangzi Jiang Wen-Zhen He Min huang yi-Li Xu Ling Liu yu-Chen Sun Mi Yang Qi Guo Yan huang Tian Su Ye Xiao Wei-Shan Wang Chao Zeng Guang-Hua Lei Xiang-Hang Luo Chang-Jun Li Department of Endocrinology Endocrinology Research CenterXiangya Hospital of Central South UniversityChangshaHunan 410008China Department of Orthopaedics Xiangya Hospital of Central South UniversityChangshaHunan 410008China Department of Epidemiology and Health Statistics Xiangya School of Public HealthCentral South UniversityChangshaChina Hunan Key Laboratory of Joint Degeneration and Injury ChangshaHunan 410008China Key Laboratory of Aging-related Bone and Joint Diseases Prevention and Treatment Ministry of EducationXiangya HospitalCentral South UniversityChangshaChina School of Biomedical Sciences Institute for Tissue Engineering and Regenerative MedicineFaculty of MedicineThe Chinese University of Hong KongHong Kong SARChina Department of Orthopaedics The First Affiliated Hospital of Shihezi UniversityShiheziXinjiangChina National Clinical Research Center for Geriatric Disorders Xiangya HospitalCentral South UniversityChangshaHunan 410008China

Skeletal stem/progenitor cell(SSPC)senescence is a major cause of decreased bone regenerative potential with aging,but the causes of SSPC senescence remain *** this study,we revealed that macrophages in calluses secrete prosenescent factors,including grancalcin(GCA),during aging,which triggers SSPC senescence and impairs fracture *** injection of human rGCA in young mice induced SSPC senescence and delayed fracture *** deletion of Gca in monocytes/macrophages was sufficient to rejuvenate fracture repair in aged mice and alleviate SSPC ***,GCA binds to the plexin-B2 receptor and activates Arg2-mediated mitochondrial dysfunction,resulting in cellular *** of Plxnb2 in SSPCs impaired fracture *** of GCA-neutralizing antibody enhanced fracture healing in aged ***,our study revealed that senescent macrophages within calluses secrete GCA to trigger SSPC secondary senescence,and GCA neutralization represents a promising therapy for nonunion or delayed union in elderly individuals.

关键词： healing union senescence