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Experimental study on wax deposition of highly paraffinic oil in intermittent gas-oil flow in pipelines

Petroleum Science 2024年第3期21卷 2080-2088页

作者： Chuan-shuo wang Qian-Li Ma Xiao-Fang Lv Jie Zhang Yang Liu Shi-Dong Zhou Jiangsu Key Laboratory of Oil and Gas Storage and Transportation Technology Changzhou UniversityChangzhou213164JiangsuPR China Hade Oil and Gas Development Department Tarim Oilfield BranchKorla841000XinjiangPR China

Oil-gas two phase wax deposition is a fairly common and open-ended question in flow assurance of multiphase transportation *** paper investigated the two main aspects of oil-gas two phase wax deposition layer:apparent thickness and crystal structure characteristics.A typical highly paraffinic oil in Bohai Sea,China,was used as the experimental material to investigate the wax deposition thickness in oil-gas two phase under the influence of different oil temperatures,superficial gas/liquid phase velocities and gas-oil ratios by using multiphase flow loop experimental *** as in the classical theory of wax molecular diffusion,it showed that wax deposition thickness of oil-gas two phase increased with increasing oil *** of the impact of different superficial phase velocities found that the actual liquid flow heat transfer and shear stripping was the gas phase dominant mechanisms determining wax deposit *** addition,the crystal structure of the wax deposition layer was characterized with the help of small-angle X-ray scattering(SAXS)for different circumferential positions,flow rates and gas-oil *** bottom deposition layer had a complex crystal structure and high hardness,which were subject to change over flow rate ***,the SAXS results provided evidence that the indirect effect of the actual liquid velocity modified by the gas phase was the main *** study of the effect of gas phase on the wax deposition of oil-gas two phase will help shed light onto the mechanism by which this important process *** findings address a very urgent need in the field of wax deposition of highly paraffinic oil to understand the flow security of oilgas two phase that occurs easily in multiphase field pipelines.

关键词： Oil-gas two phase Highly paraffinic oil Wax deposition SAXS

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Bird specimen number linked with species trait and climate niche breadth

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Avian Research 2024年第1期15卷 108-115页

作者： Xiaoyu Duan Xiongwei Huang Jingya Zhang shuo Lv Gang Song Yanping wang Gang Feng Ministry of Education Key Laboratory of Ecology and Resource Use of the Mongolian Plateau&Inner Mongolia Key Laboratory of Grassland Ecology School of Ecology and EnvironmentInner Mongolia UniversityHohhot010020China Key Laboratory of Marine Biotechnology of Fujian Province Institute of OceanologyCollege of Marine SciencesFujian Agriculture and Forestry UniversityFuzhou350002China Key Laboratory of Zoological Systematics and Evolution Institute of ZoologyChinese Academy of SciencesBeijing100101China Laboratory of Island Biogeography and Conservation Biology College of Life SciencesNanjing Normal UniversityNanjing210023China

Biological specimens are fundamental for taxonomy and flora/fauna *** importantly,they also play crucial roles in recording environmental impacts on morphology and behavior,which is vital for biodiversity research and ***,there are few systematic studies on the patterns and drivers of bird specimen number at regional *** study is the first attempt to examine the relationships between bird specimen number and species traits as well as climate niche breadth in China,aiming to answer two questions:1)how do species’temperature niche breadth and precipitation niche breadth influence specimen number?2)which trait is most associated with bird specimen number?The associations between bird specimen number and explanatory variables were examined using ordinary least squares,generalized linear models,phylogenetic generalized linear mixed models,and multiple *** results showed that Muscicapidae was the family with the highest specimen number,and Passeriformes was the order with the highest specimen *** specimen number significantly increased with larger temperature niche breadth and precipitation niche *** number was also positively associated with geographic range size,habitat specificity,hunting vulnerability and clutch size,but negatively associated with body *** findings suggest that future bird specimen collection should pay more attention to birds with limited ecological niches,large body sizes,and small clutch *** research enhances the use of bird specimen data to study and preserve biodiversity.

关键词： Biodiversity conservation Biological specimens Bird traits Scientific collection Specimen number Temperature and precipitation

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Preparation and Swelling Kinetic Analysis of Poly (HPMC-co-AA-co-AM) Super Absorbent Resin

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Journal of Wuhan University of Technology(Materials Science) 2024年第3期39卷 790-799页

作者：马砺 wang Xin LIU Xixi WEI Gaoming GUO ying School of Safety Science and Engineering Xi’an University of Science and TechnologyXi'an 710054China Key Laboratory of Coal Fire Disaster Prevention Xi’an University of Science and TechnologyXi'an 710054China School of Energy Engineering Xi’an Uni-versity of Science and TechnologyXi'an 710054China Yanzhou Coal Mining Co. Ltd.Zoucheng 237500China

Super absorbent resin(SAR)is prepared by aqueous high temperature polymerization using hydroxypropyl methylcellulose(HPMC)as monomer backbone material,acrylic acid(AA)and acrylamide(AM)as the graft copolymer monomer,potassium persulfate(KPS)as the initiator to generate free radicals,and N,N`-methylenebisacrylamide(MBA)as cross-linking agent for cross-linking ***,the influence of individual factors on the water absorption is investigated,and these factors are mainly AA,AM,KPS,MBA,HPMC,and reaction *** optimized conditions are obtained by the experiment repeating for several *** water absorption multiplicity and salt absorption multiplicity under the conditions are 782.4 and 132.5 g/g,***,the effects of different temperatures and salt concentrations on its water absorption,as well as the swelling kinetics of SAR are *** is indicated the water-absorbing swelling process is mainly caused by the difference in water osmotic pressure and Na+concentration inside and outside the cross-linked molecular structure of the resin,which is not only consistent with the quasi-secondary kinetic model,but also with the Fick diffusion model.

关键词： super absorbent resin swelling kinetics water absorption graft copolymerization hydroxypropyl methyl cellulose

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The Squeeze & Excitation Normalization Based nnU-Net for Segmenting Head & Neck Tumors

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Chinese Journal of Electronics 2024年第3期33卷 766-775页

作者： Juanying XIE ying PENG Mingzhao wang School of Computer Science Shaanxi Normal University

Head and neck cancer is one of the most common malignancies in the *** propose SE-nnU-Net by adapting SE(squeeze and excitation) normalization into nnU-Net,so as to segment head and neck tumors in PET/CT images by combining advantages of SE capturing features of interest regions and nnU-Net configuring itself for a specific *** basic module referred to convolution-ReLU-SE is designed for *** the encoder it is combined with residual structure while in the decoder without residual *** loss function combines Dice loss and Focal *** specific data preprocessing and augmentation techniques are developed,and specific network architecture is ***,the deep supervised mechanism is introduced to calculate the loss function using the last four layers of the decoder of *** SE-nnU-net is applied to HECKTOR 2020 and HECKTOR 2021 challenges,respectively,using different experimental *** experimental results show that SE-nnU-Net for HECKTOR 2020 obtained 0.745,0.821,and 0.725 in terms of Dice,Precision,and Recall,respectively,while the SE-nnU-Net for HECKTOR 2021 obtains 0.778 and 3.088 in terms of Dice and median HD95,*** SE-nnU-Net for segmenting head and neck tumors can provide auxiliary opinions for doctors diagnoses.

关键词： Image segmentation Head Data preprocessing Artificial neural networks Network architecture Data models Neck

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KeyEE:Enhancing Low-Resource Generative Event Extraction with Auxiliary Keyword Sub-Prompt

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Big Data Mining and Analytics 2024年第2期7卷 547-560页

作者： Junwen Duan Xincheng Liao ying An Jianxin wang Hunan Key Laboratory of Bioinformatics School of Computer Science and EngineeringCentral South UniversityChangsha 410083China Big Data Institute Central South UniversityChangsha 410083China

Event Extraction(EE)is a key task in information extraction,which requires high-quality annotated data that are often costly to *** classification-based methods suffer from low-resource scenarios due to the lack of label semantics and fine-grained *** recent approaches have endeavored to address EE through a more data-efficient generative process,they often overlook event keywords,which are vital for *** tackle these challenges,we introduce KeyEE,a multi-prompt learning strategy that improves low-resource event extraction by Event Keywords Extraction(EKE).We suggest employing an auxiliary EKE sub-prompt and concurrently training both EE and EKE with a shared pre-trained language *** the auxiliary sub-prompt,KeyEE learns event keywords knowledge implicitly,thereby reducing the dependence on annotated ***,we investigate and analyze various EKE sub-prompt strategies to encourage further research in this *** experiments on benchmark datasets ACE2005 and ERE show that KeyEE achieves significant improvement in low-resource settings and sets new state-of-the-art results.

关键词： natural language processing Event Extraction(EE) Multi-Prompt Learning(MPL) low-resource

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Robust blind image watermarking based on interest points

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虚拟现实与智能硬件（中英文） 2024年第4期6卷 308-322页

作者： Zizhuo wang Kun HU Chaoyangfan HUANG Zixuan HU shuo YANG Xingjun wang Tsinghua Shenzhen International Graduate School Tsinghua UniversityShenzhen 518071China

Digital watermarking technology plays an essential role in the work of anti-counterfeiting and ***,image watermarking algorithms are weak against hybrid attacks,especially geometric attacks,such as cropping attacks,rotation attacks,*** propose a robust blind image watermarking algorithm that combines stable interest points and deep learning networks to improve the robustness of the watermarking algorithm ***,to extract more sparse and stable interest points,we use the Superpoint algorithm for generation and design two steps to perform the screening *** first keep the points with the highest possibility in a given region to ensure the sparsity of the points and then filter the robust interest points by hybrid attacks to ensure high *** message is embedded in sub-blocks centered on stable interest points using a deep learning-based *** kinds of attacks and simulated noise are added to the adversarial training to guarantee the robustness of embedded *** use the ConvNext network for watermark extraction and determine the division threshold based on the decoded values of the unembedded *** extensive experimental results,we demonstrate that our proposed algorithm can improve the accuracy of the network in extracting information while ensuring high invisibility between the embedded image and the original cover *** with previous SOTA work reveals that our algorithm can achieve better visual and numerical results on hybrid and geometric attacks.

关键词： Blind watermarking Robust region selection Geometric distortion Deep learning

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Frequency and size change of ice–snow avalanches in the central Himalaya:A case from the Annapurna Ⅱ glacier

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Advances in Climate Change Research 2024年第3期15卷 464-475页

作者： Yao LI Yi-Fei CUI Jian-Sheng HAO Zheng-Tao ZHANG Hao wang Jian GUO shuo-Fan wang State Key Laboratory of Hydroscience and Engineering Department of Hydraulic EngineeringTsinghua UniversityBeijing 100084China Key Laboratory of Hydrosphere Sciences of the Ministry of Water Resources Beijing 100084China Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China School of National Safety and Emergency Management Beijing Normal UniversityBeijing 100875China Key Laboratory of Mountain Hazards and Earth Surface Process Institute of Mountain Hazards and EnvironmentChinese Academy of SciencesChengdu 610041China

Glaciers have retreated and shrunk in High Mountain Asia since the mid-20th century because of global warming,leading to glacier instability and hazardous iceesnow ***,the complex relationship between iceesnow avalanches and factors such as climate and potential triggers are difficult to understand because of the lack of observational ***,we addressed iceesnow avalanches on the Annapurna Ⅱ glacier in Nepal,Central *** constructed an iceesnow avalanche history using long-term multi-source remote sensing images(1988-2021)and mapped the velocity fields of glaciers using cross-correlation analysis on SAR and optical ***,we investigated the impact of climate change and earthquakes on the frequency and size of iceesnow *** results demonstrate that the frequency of iceesnow avalanches has increased from 10 in 1988 to 27 in 2020,but the average area of iceesnow avalanche deposits has decreased by approximately 70%,from 3.4×10^(5) m^(2) in 1988 to 1.2×10^(5) m^(2) in *** evolutionary characteristic of ice avalanches is linked to the impact of glacier retreat(reduction in ice material supply)and increased activity under climate *** glacier movement velocity controls the size of iceesnow avalanches and can be set as an indicator for iceesnow avalanche *** the Annapurna Ⅱ glacier,an iceesnow avalanche occurred when the glacier velocities were greater than 1.5 m d^(-1).These results offer insights into iceesnow avalanche risk assessment and prediction in high-mountain areas,particularly in regions characterised by dense glacier distribution.

关键词： Iceesnow avalanche Glacier instability Climate change Central Himalaya Remote sensing

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Tirofiban combined with Aspirin in the Treatment of Acute Penetrating Artery Territory Infarction (STRATEGY): protocol for a multicentre, randomised controlled trial

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Stroke & Vascular Neurology 2024年第1期9卷 75-81,I0047-I0052页

作者： Xiaoling Liao shuo Feng Yicong wang Yuesong Pan Weiqi Chen Hui Qu Xingquan Zhao Liping Liu Yongjun wang Yilong wang Department of Neurology Beijing Tiantan HospitalCapital Medical UniversityBeijingChina China National Clinical Research Center for Neurological Diseases Beijing TiantanHospitalCapital Medical UniversityBeijingChina Chinese Institute for Brain Research BeijingChina National Center for Neurological Diseases BeijingChina Advanced Innovation Center for Human Brain Protection Capital Medical UniversityBeijingChina Beijing Laboratory of Oral Health Capital Medical UniversityBeijingChina

Background Perforating artery territorial infarction(PAI)caused by branch atheromatous disease(BAD)is prone to recurrence and early progression without an effective and well-documented antiplatelet treatment ***,an adjunctive antiplatelet agent,has shown great potential to treat acute ischaemic ***,whether the combination of tirofiban and aspirin can improve the prognosis of PAI remains *** To explore an effective and safe antiplatelet regimen for reducing the risk of recurrence and early neurological deterioration(END)in PAI caused by BAD by comparing the tirofiban and aspirin combination with placebo and aspirin *** Tirofiban combined with Aspirin in the Treatment of Acute Penetrating Artery Territory Infarction(STRATEGY)trial is an ongoing multicentre,randomised,placebo-controlled trial in *** patients shall be randomly assigned to receive standard aspirin with tirofiban or placebo on the first day and standard aspirin from days 2 to *** primary endpoint is a new stroke or END within 90 *** primary safety endpoint is severe or moderate bleeding within 90 *** The STRATEGY trial will assess whether tirofiban combined with aspirin is effective and safe in preventing recurrence and END in patients with *** registration number NCT05310968.

关键词： Aspirin regimen centre

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Optimal investment based on relative performance and weighted utility

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Applied Mathematics(A Journal of Chinese Universities) 2024年第2期39卷 328-342页

作者： wang Lei DONG ying-hui HUA Chun-rong Department of Mathematics Suzhou University of Science and TechnologySuzhou 215009China Changshu Institute of Technology Changshu 215500China

This paper studies the optimal portfolio allocation of a fund manager when he bases decisions on both the absolute level of terminal relative performance and the change value of terminal relative performance comparison to a predefined reference point. We find the optimal investment strategy by maximizing a weighted average utility of a concave utility and an Sshaped utility via a concavification technique and the martingale method. Numerical results are carried out to show the impact of the extent to which the manager pays attention to the change of relative performance related to the reference point on the optimal terminal relative performance.

关键词： relative performance weighted utility S-shaped utility concavification

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Model based on single-nucleotide polymorphism to discriminate aspirin resistance patients

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Stroke & Vascular Neurology 2024年第3期9卷 212-220,I0110-I0129页

作者： Qingyuan Liu Shuaiwei Guo Nuochuan wang Kaiwen wang Shaohua Mo Xiong Li Yanan Zhang Hongwei He shuo wang Jun Wu Department of Neurosurgery and China National Clinical Research Center for Neurological Diseases Beijing Tiantan HospitalBeijingChina Department of Blood Transfusion Beijing Tiantan HospitalBeijingChina Department of Neurosurgery Beijing Chao-Yang Hospital Capital Medical UniversityBeijingChina Beijing Neurosurgical institution Capital Medical UniversityBeijingChina

Background Aspirin is widely used for preventing ischaemic *** 20%–40%of patients have aspirin resistance(ASR),which prevents them from benefiting from aspirin *** study aimed to develop and validate a model based on single-nucleotide polymorphism(SNP)to distinguish ASR *** We included patients with spontaneous intracerebral haemorrhage and continuing antiplatelet therapy from a multicentre,prospective cohort study as the derivation ***(inhibition of arachidonic acid channel<50%)was used to identify *** was performed to identify the ASR-related *** on the result of the logistic analysis,the aspirin resistance in the Chinese population score(ASR-CN score)was established,and its accuracy was evaluated using the area under the curve(AUC).Patients receiving dual antiplatelet therapy for unruptured intracranial aneurysm embolism were prospectively included in the validation *** embolism,30-day ischaemic events,including ischaemic stroke,new or more frequent transient ischaemic attack,stent thrombosis and cerebrovascular death,were *** The derivation cohort included 212 patients(155 male patients and the median age as 59).87(41.0%)individuals were identified with *** multivariate logistic analysis demonstrated six SNPs of GP1BA,TBXA2R,PTGS2 and NOS3 as risk factors related to *** ASR-CN score integrating these SNPs performed well to discriminate ASR patients from non-ASR patients(AUC as 0.77).Based on the validation cohort of 372 patients receiving antiplatelet therapy after embolism(including 130 ASR patients),the ASR-CN score continued to distinguish ASR patients with good accuracy(AUC as 0.80).Patients with high a ASR-CN score were more likely to suffer from 30-day ischaemic events after embolism(OR,1.28;95%CI,1.10 to 1.50;p=0.002).Conclusion GP1BA,TBXA2R,PTGS2 and NOS3 were SNPs related to *** ASR-CN score is an effective tool to discriminate ASR patients,which

关键词： patients aspirin resistance

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