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Accurate simulations of pure-viscoacoustic wave propagation in tilted transversely isotropic media

Petroleum Science 2024年第2期21卷 866-884页

作者： Qiang Mao Jian-Ping Huang Xin-Ru Mu Ji-Dong Yang Yu-Jian zhang Geosciences Department China University of Petroleum(East China)Qingdao266580ShandongChina Pilot National Laboratory for Marine Science and Technology(Qingdao) Qingdao266207ShandongChina

Forward modeling of seismic wave propagation is crucial for the realization of reverse time migration(RTM) and full waveform inversion(FWI) in attenuating transversely isotropic media. To describe the attenuation and anisotropy properties of subsurface media, the pure-viscoacoustic anisotropic wave equations are established for wavefield simulations, because they can provide clear and stable wavefields. However, due to the use of several approximations in deriving the wave equation and the introduction of a fractional Laplacian approximation in solving the derived equation, the wavefields simulated by the previous pure-viscoacoustic tilted transversely isotropic(TTI) wave equations has low accuracy. To accurately simulate wavefields in media with velocity anisotropy and attenuation anisotropy, we first derive a new pure-viscoacoustic TTI wave equation from the exact complex-valued dispersion formula in viscoelastic vertical transversely isotropic(VTI) media. Then, we present the hybrid finite-difference and low-rank decomposition(HFDLRD) method to accurately solve our proposed pure-viscoacoustic TTI wave equation. Theoretical analysis and numerical examples suggest that our pure-viscoacoustic TTI wave equation has higher accuracy than previous pure-viscoacoustic TTI wave equations in describing q P-wave kinematic and attenuation characteristics. Additionally, the numerical experiment in a simple two-layer model shows that the HFDLRD technique outperforms the hybrid finite-difference and pseudo-spectral(HFDPS) method in terms of accuracy of wavefield modeling.

关键词： Pure-viscoacoustic TTI wave equation Attenuation anisotropy Seismic modeling Low-rank decomposition method

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Multispectral point cloud superpoint segmentation

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Science China(Technological Sciences) 2024年第4期67卷 1270-1281页

作者： WANG QingWang WANG MingYe zhang ZiFeng SONG Jian ZENG Kai SHEN Tao GU YanFeng Faculty of Information Engineering and Automation Kunming University of Science and TechnologyKunming 650500China Yunnan Key Laboratory of Computer Technologies Application Kunming 650500China School of Electronics and Information Engineering Harbin Institute of TechnologyHarbin 150001China

The multitude of airborne point clouds limits the point cloud processing *** are grouped based on similar points,which can effectively alleviate the demand for computing resources and improve processing ***,existing superpoint segmentation methods focus only on local geometric structures,resulting in inconsistent spectral features of points within a *** feature inconsistencies degrade the performance of subsequent ***,this study proposes a novel Superpoint Segmentation method that jointly utilizes spatial Geometric and Spectral Information for multispectral point cloud superpoint segmentation(GSI-SS).Specifically,a similarity metric that combines spatial geometry and spectral information is proposed to facilitate the consistency of geometric structures and object attributes within segmented *** the formation of the primary superpoints,an intersuperpoint pointexchange mechanism that maximizes feature consistency within the final superpoints is *** are conducted on two real multispectral point cloud datasets,and the proposed method achieved higher recall,precision,F score,and lower global consistency and feature classification *** experimental results demonstrate the superiority of the proposed GSI-SS over several state-of-the-art methods.

关键词： multispectral point cloud superpoint segmentation over-segmentation spatial-spectral joint metric

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Sequential good lattice point sets for computer experiments

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Science China Mathematics 2024年第9期67卷 2153-2170页

作者： Xue-Ru zhang Yong-Dao Zhou Min-Qian Liu Dennis K.J.Lin NITFID LPMC & KLMDASR School of Statistics and Data Science Nankai University Department of Statistics Purdue University

Sequential Latin hypercube designs(SLHDs) have recently received great attention for computer experiments, with much of the research restricted to invariant spaces. The related systematic construction methods are inflexible, and algorithmic methods are ineffective for large designs. For designs in contracting spaces, systematic construction methods have not been investigated yet. This paper proposes a new method for constructing SLHDs via good lattice point sets in various experimental spaces. These designs are called sequential good lattice point(SGLP) sets. Moreover, we provide efficient approaches for identifying the(nearly)optimal SGLP sets under a given criterion. Combining the linear level permutation technique, we obtain a class of asymptotically optimal SLHDs in invariant spaces, where the L1-distance in each stage is either optimal or asymptotically optimal. Numerical results demonstrate that the SGLP set has a better space-filling property than the existing SLHDs in invariant spaces. It is also shown that SGLP sets have less computational complexity and more adaptability.

关键词： contracting space maximin distance nested Latin hypercube design sequential design space-filling design

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LKPNR: Large Language Models and Knowledge Graph for Personalized News Recommendation Framework

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Computers, Materials & Continua 2024年第6期79卷 4283-4296页

作者： Hao Chen Runfeng Xie Xiangyang Cui Zhou Yan Xin Wang Zhanwei Xuan Kai zhang State Key Laboratory of Communication Content Cognition People’s Daily OnlineBeijing100733China

Accurately recommending candidate news to users is a basic challenge of personalized news recommendation *** methods are usually difficult to learn and acquire complex semantic information in news texts,resulting in unsatisfactory recommendation ***,these traditional methods are more friendly to active users with rich historical ***,they can not effectively solve the long tail problem of inactive *** address these issues,this research presents a novel general framework that combines Large Language Models(LLM)and Knowledge Graphs(KG)into traditional *** learn the contextual information of news text,we use LLMs’powerful text understanding ability to generate news representations with rich semantic information,and then,the generated news representations are used to enhance the news encoding in traditional *** addition,multi-hops relationship of news entities is mined and the structural information of news is encoded using KG,thus alleviating the challenge of long-tail *** results demonstrate that compared with various traditional models,on evaluation indicators such as AUC,MRR,nDCG@5 and nDCG@10,the framework significantly improves the recommendation *** successful integration of LLM and KG in our framework has established a feasible way for achieving more accurate personalized news *** code is available at https://***/Xuan-ZW/LKPNR.

关键词： Large language models news recommendation knowledge graphs(KG)

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Association of prealbumin with short-term and long-term outcomes in patients with acute ST-segment elevation myocardial infarction

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Journal of Geriatric Cardiology 2024年第4期21卷 421-430页

作者： Jing TAN Jin SI Ke-Ling XIAO Ying-Hua zhang Qi HUA Jing LI Department of Cardiology Xuanwu Hospital Capital Medical UniversityBeijingChina Department of Geriatric Medicine Xuanwu Hospital Capital Medical UniversityNational Clinical Research Center for Geriatric DiseasesBeijingChina

BACKGROUND Prealbumin is considered to be a useful indicator of nutritional status. Furthermore, it has been found to be associated with severities and prognosis of a range of diseases. However, limited data on the association of baseline prealbumin level with outcomes of patients with acute ST-segment elevation myocardial infarction(STEMI) are *** We analyzed 2313 patients admitted for acute STEMI between October 2013 and December 2020. In-hospital outcomes and mortality during the 49 months(interquartile range: 26–73 months) follow-up period were compared between patients with the low prealbumin level(< 170 mg/L) and those with the high prealbumin level(≥ 170 mg/L).RESULTS A total of 114 patients(4.9%) died during hospitalization. After propensity score matching, patients with the low prealbumin level than those with the high prealbumin level experienced higher incidences of heart failure with Killip class Ⅲ(9.9%vs. 4.4%, P = 0.034), cardiovascular death(8.4% vs. 3.4%, P = 0.035) and the composite of major adverse cardiovascular events(19.2%vs. 10.3%, P = 0.012). Multivariate logistic regression analysis identified that the low prealbumin level(< 170 mg/L) was an independent predictor of in-hospital major adverse cardiovascular events(odds ratio = 1.918, 95% CI: 1.250–2.942, P = 0.003). The cutoff value of prealbumin level for predicting in-hospital death was 170 mg/L(area under the curve = 0.703, 95% CI: 0.651–0.754, P< 0.001;sensitivity = 0.544, specificity = 0.794). However, after multivariate adjustment of possible confounders, baseline prealbumin level(170 mg/L) was no longer independently associated with 49-month cardiovascular death. After propensity score matching, Kaplan-Meier survival curves revealed consistent *** Decreased prealbumin level closely related to unfavorable short-term outcomes. However, after multivariate adjustment and controlling for baseline differences, baseline prealbumin level was not independently assoc

关键词： patients admitted infarction

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A review of ultra-high temperature heat-resistant energetic materials

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Defence Technology（防务技术） 2024年第8期38卷 33-57页

作者： Rongzheng zhang Yuangang Xu Feng Yang Pengcheng Wang Qiuhan Lin Hui Huang Ming Lu School of Chemistry and Chemical Engineering Nanjing University of Science and TechnologyNanjing 210094China Institute of Chemical Materials China Academy of Engineering PhysicsMianyang 621900China

Heat-resistant energetic materials refer to a type of energetic materials that possess a high melting point,high stability and operational safety. By studying the structures of these energetic materials has showed that the thermal stability can be enhanced by introducing amino groups to form intra/inter-molecular hydrogen bonds, constructing conjugate systems and designing symmetrical structures. This article aims to review the physical and chemical properties of ultra-high temperature heat-resistant energetic compounds and provide valuable theoretical insights for the preparation of ultra-high temperature heatresistant energetic materials. We also analyze the selected 20 heat-resistant energetic materials with decomposition temperatures higher than 350℃, serving as templates for the synthesis of various highperformance heat-resistant energetic materials.

关键词： Heat-resistant energetic materials Organic synthesis Conjugated Hydrogen bond Symmetrical structure Stabilization

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Fabrication of telechelic DNA-bridged food emulsion gel as edible ink for 3D printing

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Food Quality and Safety 2024年第1期8卷 158-165页

作者： Ruyuan zhang Hao Huang Rong Ai Dong Li Yanqun Xu Weiwei Jin Zisheng Luo College of Biological Chemical Sciences and Engineering Jiaxing UniversityJiaxingChina College of Biosystems Engineering and Food Science Zhejiang UniversityHangzhouChina College of Ecology Lishui UniversityLishuiChina Ningbo Innovation Center Zhejiang UniversityNingboChina Wenzhou Academy of Agriculture Science Liuhongqiao Road 1000WenzhouChina Key Laboratory of Agro-Products Postharvest Handling of Ministry of Agriculture and Rural Affairs Zhejiang Key Laboratory for Agri-Food ProcessingHangzhouChina

Objectives:Interdroplet interactions affect the properties and textures of *** this study,we creatively introduced telechelic DNA to link oil droplets directly at molecular scale to further improve the viscoelastic properties of *** and Methods:A stable emulsion with 70%oil fraction was prepared by adding 40 mg/mL of whey protein isolate and peach gum polysaccharide complex(WPI–PGP complex).The addition of telechelic DNA(0.125–0.375μmol/L)made the emulsion change from a cream-like state to a self-supporting ***:Rheological experiments confirmed that the telechelic DNA could improve the yield stress,storage modulus/loss modulus(Gʹ/Gʹʹ)and apparent viscosity of the emulsion gel in a concentration-dependent manner(0–0.375μmol/L).Inverted fluorescence images clearly showed the interdroplet network of the emulsion gel linked by telechelic *** 3D printing,the emulsion gel with a higher concentration(0.375μmol/L)of telechelic DNA displayed better surface quality and dimensional resolution,indicating improved ***:This study successfully designed a novel telechelic DNA-bridged emulsion gel,which showed great potential as edible ink for 3D printing.

关键词： Telechelic DNA WPI-PGP complex emulsion gel interdroplet interactions 3D printing.

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Fabricating a smart clothing system based on strain-sensing yarn and novel stitching technology for health monitoring

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Science China(Technological Sciences) 2024年第2期67卷 587-596页

作者： TANG Jian WU YuTing MA ShiDong zhang YuMin XU RuoJie YAN Tao PAN ZhiJuan College of Textile and Clothing Engineering Soochow UniversitySuzhou 215123China National Engineering Laboratory for Modern Silk Suzhou 215123China

Various yarn-shaped flexible strain sensors have recently been ***,research is lacking on additive manufacturing for smart clothing for integrating yarn sensors with commercial ***,a strain-sensing yarn is sewn into a piece of fabric through a novel stitching technique,and the influence of the stitching method and needle pitch on the sensing performance is investigated using finite element analysis(FEA).The sensing performance could be improved when the sensing yarn is self-locked in the fabric at the needle eyes,and the needle pitch was reduced to 0.5 cm,which is attributed to the enhanced stress and strain ***,the composite sensing fabric featured outstanding performance,including a low detection limit(0.1%),rapid response(280 ms),excellent durability(10000 cycles),and high stability(negligible drift and frequency independence).In addition,the remarkable wear resistance,washability,and anti-interference to ambient humidity and perspiration were ***,the optimal stitch trace lengths of sensing yarn for detecting elbow motion,breathing,and heartbeats are ***,a smart clothing system composed of smart clothing,data acquisition unit,and mobile APP was developed to simultaneously detect human movement and physiological *** work provides a reference to produce intelligent garments based on yarn sensors for health monitoring.

关键词： strain-sensing yarn composite sensing fabric smart clothing system stitching technology health monitoring

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Free-Standing Multiscale Porous High Entropy NiFeCoZn Alloy as the Highly Active Bifunctional Electrocatalyst for Alkaline Water Splitting

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Chinese Journal of Chemistry 2024年第13期42卷 1465-1473页

作者： Qiuping zhang Xu Wang Tianzhen Jian Wenqing Ma Caixia Xu Qiuxia Zhou Hong Liu Institute for Advanced Interdisciplinary Research(iAIR) Collaborative Innovation Center of Technology and Equipment for Biological Diagnosis and Therapy in Universities of ShandongSchool of Chemistry and Chemical EngineeringUniversity of JinanJinanShandong 250022China School of Medical Information and Engineering Southwest Medical UniversityLuzhouSichuan 646000China State Key Laboratory of Crystal Materials Shandong UniversityJinanShandong 250100China

In the endeavor of searching for highly active and stable electrocatalysts toward overall water splitting,high-entropy-alloys have been the intense subjects owing to their advanced physicochemical *** non-noble metal free-standing multiscale porous NiFeCoZn high-entropy-alloy is in situ constructed on the surface layer of NiZn intermetallic and Ni heterojunction over nickel foam(NiFeCoZn/NiZn-Ni/NF)by one scalable dealloying protocal to fulfill the outstanding bifunctional electrocatalytic performances toward overall water *** of the high-entropy effects and specific hierarchical porous architecture,the as-made NiFeCoZn/NiZn-Ni/NF displays high intrinsic catalytic activities and durability toward both hydrogen evolution reaction(HER)and oxygen evolution reaction(OER)in alkaline *** particular,the in-situ construction of bimodal porous NiFeCoZn high-entropy-alloy results in the small overpotentials(η1000=254/409 mV for HER and OER),low Tafel slopes,and exceptional long-term catalytic durability for 400 ***,the electrolyzer constructed with NiFeCoZn/NiZn-Ni/NF as both cathode and anode exhibits a low cell voltage of 1.72 V to deliver the current density of 500 mA·cm^(–2) for overall water *** work not only provides a facile and scalable protocol for the preparation of self-supporting high-entropy-alloy nanocatalysts but also enlightens the engineering of high performance bifunctional electrocatalysts toward water splitting.

关键词： High-entropy-alloys Bifunctional electrocatalyst Dealloying/Electrocatalysis Oxygen evolution reaction Hydrogen evolution reaction

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Changes in muscle strength and risk of cardiovascular disease among middle-aged and older adults in China:Evidence from a prospective cohort study

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Chinese Medical Journal 2024年第11期137卷 1343-1350页

作者： Ze Yang Jiemin Wei Hongbo Liu Honglu zhang Ruifang Liu Naijun Tang Xueli Yang Department of Occupational and Environmental Health School of Public HealthTianjin Medical UniversityTianjin 300070China Tianjin Key Laboratory of Environment Nutrition and Public HealthTianjin Medical UniversityTianjin 300070China Center for International Collaborative Research on Environment Nutrition and Public HealthTianjin 300070China

Background:Evidence indicates that low muscle strength is associated with an increased cardiovascular diseases(CVDs)***,the association between muscle strength changes based on repeated measurements and CVD incidence remains ***:The study used data from the China Health and Retirement Longitudinal Study in 2011(Wave 1),2013(Wave 2),2015(Wave 3),and 2018(Wave 4).Low muscle strength was defined as handgrip strength<28 kg for men or<18 kg for women,or chair-rising time≥12 *** on changes in muscle strength from Waves 1 to 2,participants were categorized into four groups of Normal-Normal,Low-Normal,Normal-Low,and *** events,including heart disease and stroke,were recorded using a self-reported questionnaire during Waves 3 and 4 *** proportional hazards models were used to investigate the association between muscle strength changes and CVD incidence after multivariable *** ratios(HRs)and 95%confidence intervals(95%CIs)were estimated with the Normal-Normal group as the ***:A total of 1164 CVD cases were identified among 6608 *** to participants with sustained normal muscle strength,the CVD risks increased progressively across groups of the Low-Normal(HR=1.20,95%CI:1.01-1.43),the Normal-Low(HR=1.35,95%CI:1.14-1.60),and the Low-Low(HR=1.76,95%CI:1.49-2.07).Similar patterns were observed for the significant associations between muscle strength status and the incidence risks of heart disease and *** analyses showed that the significant associations between CVD and muscle strength changes were consistent across age,sex,and body mass index(BMI)***:The study found that muscle strength changes were associated with CVD *** suggests that continuous tracking of muscle status may be helpful in screening cardiovascular risk.

关键词： Muscle strength Cardiovascular disease Prospective cohort study Aging Body mass index Sarcopenia

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