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Journal of Geriatric Cardiology 2024年第6期21卷 658-668页

作者： Wen-Jie wang Ke-Xin wang Jia-long NIU Yi-Xuan LIU Hai-long GE Hua SHEN On behalf of CCC-ACS investigators Department of Cardiology Beijing Anzhen HospitalCapital Medical UniversityBeijingChina

BACKGROUND Stress hyperglycemia ratio(SHR)could provide accurate information on the acute status of *** relationship between SHR and acute coronary syndrome(ACS)prognosis remains *** study was conducted to identity the association between SHR and in-hospital outcomes in patients with *** A total of 12,010 patients were eventually enrolled in the *** relationship between SHR and in-hospital major adverse cardiovascular events(MACEs)was then modeled by restricted cubic spline(RCS)curves,and all patients were divided into three groups according to the *** multivariate logistic regression analysis was used to determine the associations between the SHR and in-hospital outcomes,described as odds ratios(ORs)and 95%confidence intervals(CIs).Subgroup analyses were also performed on different *** The median age of this cohort was 63(54,71)years old,and 8942(74.5%)were *** 1 was defined as SHR1(n=5763).Compared with Group 2,Group 1(OR=1.891,95%CI:1.028-3.479,P<0.001)and Group 3(OR=1.868,95%CI:1.434-2.434,P<0.001)had higher risks of suffering from in-hospital *** was associated with higher risks of in-hospital MACEs in the subgroups of DM[OR=2.282,95%CI:1.477-3.524).CONCLUSIONS Both low and high SHR levels were independently associated with in-hospital *** males with DM,hypertension,and decreased renal function had much higher risks of suffering from SHR-correlated MACEs.

关键词： acute cardiovascular finding

An Efficient Task Scheduling Algorithm in the Cloud and Edge Collaborative Environment

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Chinese Journal of Electronics 2024年第5期33卷 1296-1307页

作者： Saiqin long Cong wang Weifan long Haolin LIU Qingyong DENG Zhetao LI Jinan University School of Computer Science Xiangtan University guangxi Normal University

With the advent of the 5G era and the accelerated development of edge computing and Internet of Things technologies, the number of tasks to be processed by mobile devices continues to increase. Edge nodes become incapable of facing massive tasks due to their own limited computing capabilities, and thus the cloud and edge collaborative environment is produced. In order to complete as many tasks as possible while meeting the deadline constraints, we consider the task scheduling problem in the cloud-edge and edge-edge collaboration scenarios. As the number of tasks on edge nodes increases, the solution space becomes larger. Considering that each edge node has its own communication range, we design an edge node based clustering algorithm(ENCA), which can reduce the feasible region while dividing the edge node set. We transform the edge nodes inside the cluster into a bipartite graph,and then propose a task scheduling algorithm based on maximum matching(SAMM). Our ENCA and SAMM are used to solve the task scheduling problem. Compared with the other benchmark algorithms, experimental results show that our algorithms increase the number of the tasks which can be completed and meet the latest deadline constraints by 32%–47.2% under high load conditions.

关键词： Bipartite matching Node clustering Edge-edge collaboration Cloud-edge collaboration Task scheduling Bipartite matching Node clustering Edge-edge collaboration Cloud-edge collaboration Task scheduling COMPUTATION ASSIGNMENT

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Selective nickel-electrocatalyzed benzylic C-H oxygenation of functionalized alkyl arenes

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Chinese Chemical Letters 2024年第2期35卷 396-401页

作者： Shunyao Tang Siyi wang Dongmei Zhang Xinxing Zhang guang Yang Yanwei wang Youai Qiu State Key Laboratory of Elemento-Organic Chemistry Frontiers Science Center for New Organic MatterCollege of ChemistryNankai UniversityTianjin 300071China College of Chemistry Key Laboratory of Advanced Energy Materials Chemistry (Ministry of Education)Renewable Energy Conversion and Storage Center (RECAST)Frontiers Science Center for New Organic MatterNankai UniversityTianjin 300071China

Herein, a site-selective paired electrochemical C–H oxidation of functionalized alkyl arenes promoted by nickel catalyst is disclosed. A Ni(Ⅱ)-dioxygen species formed in situ efficiently enable the oxidation process under mild conditions with a broad substrate scope with excellent functional group compatibilities,such as free carboxylic acid, aldehyde, halogen(including aryl iodide), amide and amino acid. The use of the nickel catalyst in combination with water provides a safe, green and economical method for oxidation of a range of molecules varying in complexity and drug derivatives, demonstrating its potential application in organic synthesis and the pharmaceutical industry. Reaction outcomes and mechanistic studies revealed the key role of the in situ Ni(Ⅱ)-dioxygen species for the subsequent oxidation of C(sp^(3))–H bonds,and short-lived reactive intermediates(aryl radical cation) was rapidly captured by the combination of a bipolar ultramicroelectrode(BUME) with nano-electrospray ionization mass spectrometry.

关键词： Electrochemical C-H oxidation Functionalized alkyl arenes Paired nickel-electrocatalysis H_(2)O oxidation Ketones

Numerical Study on the Aerodynamic and Fluid−Structure Interaction of An NREL-5MW Wind Turbine

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China Ocean Engineering 2024年第3期38卷 363-378页

作者： ZHAO Mi YU Wan-li wang Pi-guang QU Yang DU Xiu-li Key Laboratory of Urban Security and Disaster Engineering of Ministry of Education Beijing University of TechnologyBeijing 100124China State Key Laboratory of Bridge Engineering Safety and Resilience Beijing University of TechnologyBeijing 100124China

A 5-MW wind turbine has been modeled and analyzed for fluid-structure interaction and aerodynamic *** this study, a full-scale model of a 5-MW wind turbine is first developed based on a computational fluid dynamics(CFD) approach, in which the unsteady, noncompressible Reynolds Averaged Navier-Stokes(RANS) method is used. The main focus of the study is to analyze the tower shadow effect on the aerodynamic performance of the wind turbine under different inlet flow conditions. Subsequently, the finite element model is established by considering fluid/structure interactions to study the structural stress, displacement, strain distributions and flow field information of the structure under the uniform wind speed. Finally, the fluid-structure interaction model is established by considering turbulent wind and the tower shadow effect. The variation rules of the dynamic response of the one-way and two-way fluid-structure interaction(FSI) models under different wind speeds are analyzed, and the numerical calculation results are compared with those of the centralized mass model. The results show that the tower shadow effect and structural deformation are the main factors affecting the aerodynamic load fluctuation of the wind turbine, which in turn affects the aerodynamic performance and structural stability of the blades. The structural dynamic response of the coupled model shows significant similarity, while the structural displacement response of the former exhibits less fluctuation compared with the conventional centralized mass model. The one-way fluid-structure interaction(FSI)model shows a higher frequency of stress-strain and displacement oscillations on the blade compared with the two-way FSI model.

关键词： computational fluid dynamics methods(CFD) tower shadow effect aerodynamic performance fluidstructure interaction space flow field

How interfacial electron-donating defects influence the structure and charge of gold nanoparticles on TiO_(2)support

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Nano Research 2024年第7期17卷 5965-5974页

作者： guang-Jie Xia Yu Fu Wei Cao Jun Li Yang-Gang wang Department of Chemistry and guangdong Provincial Key Laboratory of Catalysis Southern University of Science and TechnologyShenzhen 518055China School of Physical Sciences Great Bay UniversityDongguan 523000China Department of Chemistry Tsinghua UniversityBeijing 100084China

The reduction degree of TiO_(2)support is critical to the performances of metal *** many previous theoretical calculations,only the bridge oxygen vacancy(Ov)was considered as the electron-donating defect on reduced rutile TiO_(2)(r-TiO_(2−x))***,titanium adatoms(Tiad.),oxidized titanium islands(***),and acid hydroxyls(ObrH)also exist at the metal/support *** conducting density functional theory(DFT)calculations and ab initio molecular dynamics(AIMD)simulations,we compared r-TiO_(2−x)surfaces with Ov,Tiad.,***,and ObrH sites loaded with Au nanoparticles(NPs).The results showed the Au NPs were oxygen-phobic but titanium-philic,resulting in wetting of Ov and *** short contact with *** and *** Bader charges of Au NPs(QM)showed a good linear relationship with the ideal number of donating electrons(Ne)from the defective sites(QM=−KeNe+QM,S),demonstrating the intrinsic electron allocation at the *** Ov,Tiad.,and *** exhibited similar slopes(Ke),relatively steeper than that of *** means in the scope of Au NP charge state,the *** *** have a close electron-donating ability with Ov,but the ObrH donates relatively fewer *** linear relationship can be extended approximately to other *** higher the metal work function,the steeper the Ke for easier electron donation from defective *** stronger the metal oxygen affinity,the more positive the intercept(QM,S).That explains the easy generation of metallic or negative Pt and Au NPs on r-TiO_(2−x),but hard for Cu and Zn in *** provides theoretical guidance for regulating the charge of metal NPs over TiO_(2−x)supports.

关键词： metal-support interaction titanium oxide oxygen vacancy surface hydroxyl titanium adatom

Significant risk factors for intensive care unit-acquired weakness:A processing strategy based on repeated machine learning

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World Journal of Clinical Cases 2024年第7期12卷 1235-1242页

作者： Ling wang Deng-Yan long Intensive Care Unit People's Hospital of Qiandongnan Miao and Dong Autonomous PrefectureKaili 556000Guizhou ProvinceChina

BACKGROUND Intensive care unit-acquired weakness(ICU-AW)is a common complication that significantly impacts the patient's recovery process,even leading to adverse ***,there is a lack of effective preventive *** To identify significant risk factors for ICU-AW through iterative machine learning techniques and offer recommendations for its prevention and *** Patients were categorized into ICU-AW and non-ICU-AW groups on the 14th day post-ICU *** data from the initial 14 d of ICU stay,such as age,comorbidities,sedative dosage,vasopressor dosage,duration of mechanical ventilation,length of ICU stay,and rehabilitation therapy,were *** relationships between these variables and ICU-AW were *** iterative machine learning techniques,a multilayer perceptron neural network model was developed,and its predictive performance for ICU-AW was assessed using the receiver operating characteristic *** Within the ICU-AW group,age,duration of mechanical ventilation,lorazepam dosage,adrenaline dosage,and length of ICU stay were significantly higher than in the non-ICU-AW ***,sepsis,multiple organ dysfunction syndrome,hypoalbuminemia,acute heart failure,respiratory failure,acute kidney injury,anemia,stress-related gastrointestinal bleeding,shock,hypertension,coronary artery disease,malignant tumors,and rehabilitation therapy ratios were significantly higher in the ICU-AW group,demonstrating statistical *** most influential factors contributing to ICU-AW were identified as the length of ICU stay(100.0%)and the duration of mechanical ventilation(54.9%).The neural network model predicted ICU-AW with an area under the curve of 0.941,sensitivity of 92.2%,and specificity of 82.7%.CONCLUSION The main factors influencing ICU-AW are the length of ICU stay and the duration of mechanical ventilation.A primary preventive strategy,when feasible,involves minimizing both ICU stay and mechani

关键词： Intensive care unit-acquired weakness Risk factors Machine learning Prevention Strategies

Enhanced Sensing Mechanism Based on Shifting an Exceptional Point

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Research 2024年第3期6卷 285-292页

作者： Xuan Mao Guo-Qing Qin Hao Zhang Bo-Yang wang Dan long Gui-Qin Li Gui-Lu long Department of Physics State Key Laboratory of Low-Dimensional Quantum PhysicsTsinghua UniversityBeijing 100084China Beijing Institute of Radio Measurement The Second Academy of China Aerospace Science and Industry Corporation(CASIC)Beijing 100854China Purple Mountain Laboratories Nanjing 21111China Frontier Science Center for Quantum Information Beijing 100084China Beijing Academy of Quantum Information Sciences Beijing 100193China

Non-Hermitian systems associated with exceptional points (EPs) are expected to demonstrate a giant response enhancement for various sensors. The widely investigated enhancement mechanism based on diverging from an EP should destroy the EP and further limits its applications for multiple sensing scenarios in a time sequence. To break the above limit, here, we proposed a new enhanced sensing mechanism based on shifting an EP. Different from the mechanism of diverging from an EP, our scheme is an EP nondemolition and the giant enhancement of response is acquired by a slight shift of the EP along the parameter axis induced by perturbation. The new sensing mechanism can promise the most effective response enhancement for all sensors in the case of multiple sensing in a time sequence. To verify our sensing mechanism, we construct a mass sensor and a gyroscope with concrete physical implementations. Our work will deepen the understanding of EP-based sensing and inspire designing various high-sensitivity sensors in different physical systems.

关键词： mechanism shifting exceptional

A systematic framework of constructing surrogate model for slider track peeling strength prediction

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Science China Technological Sciences 2024年第10期67卷 3261-3274页

作者： DONG XingJian CHEN Qian LIU WenBo wang Dong PENG ZhiKe MENG guang State Key Laboratory of Mechanical System and Vibration Shanghai Jiao Tong University KEIPER Seating Mechanisms Co. Ltd. Department of Industrial Engineering and Management Shanghai Jiao Tong University

Peeling strength can comprehensively reflect slider track safety and is crucial in car seat safety assessments. Current methods for determining slider peeling strength are primarily physical testing and numerical simulation. However, these methods encounter the potential challenges of high costs and overlong time consumption which have not been adequately addressed. Therefore, the efficient and low-cost surrogate model emerges as a promising solution. Nevertheless, currently used surrogate models suffer from inefficiencies and complexity in data sampling, lack of robustness in local model predictions, and isolation between data sampling and model prediction. To overcome these challenges, this paper aims to set up a systematic framework for slider track peeling strength prediction, including sensitivity analysis, dataset sampling, and model prediction. Specifically, the interpretable linear regression is performed to identify the sensitivity of various geometric variables to peeling strength. Based on the variable sensitivity, a distance metric is constructed to measure the disparity of different variable groups. Then, the sparsity-targeted sampling(STS) is proposed to formulate a representative dataset. Finally, the sequentially selected local weighted linear regression(SLWLR) is designed to achieve accurate track peeling strength prediction. Additionally, a quantitative cost assessment of the supplementary dataset is proposed by utilizing the minimum adjacent sample distance as a mediator. Experimental results validate the efficacy of sequential selection and the weighting mechanism in enhancing localization ***, the proposed SLWLR method surpasses similar approaches and other common surrogate methods in terms of prediction performance and data quantity requirements, achieving an average absolute error of 3.3 kN in the simulated test dataset.

关键词： slider track peeling strength surrogate model sensitivity analysis data sampling local weighted linear regression

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Analytical Solution and Simplified Formula for Added Mass of Horizontal and Vertical Motions of Truncated Cylinders Under Earthquake Action

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China Ocean Engineering 2024年第1期38卷 54-67页

作者： wang Pi-guang LYU Si-yu QU Yang ZHAO Mi DU Xiu-li State Key Laboratory of Bridge Engineering Safety and Resilience Beijing University of TechnologyBeijing 100124China Key Laboratory of Urban Security and Disaster Engineering of Ministry of Education Beijing University of Tech-nologyBeijing 100124China

This paper investigates the hydrodynamic characteristics of floating truncated cylinders undergoing horizontal and vertical motions due to earthquake excitations in the finite water *** governing equation of the hydrodynamic pressure acting on the cylinder is derived based on the radiation theory with the inviscid and incompressible *** governing equation is solved by using the method of separating variables and analytical solutions are obtained by assigning reasonable boundary *** analytical result is validated by a numerical model using the exact artificial boundary simulation of the infinite *** main variation and distribution characteristics of the hydrodynamic pressure acting on the side and bottom of the cylinder are analyzed for different combinations of wide-height and immersion *** added mass coefficient of the cylinder is calculated by integrating the hydrodynamic pressure and simplified formulas are proposed for engineering *** calculation results show that the simplified formulas are in good agreement with the analytical solutions.

关键词： earthquake hydrodynamic pressure truncated cylinder added mass simplified formula

Damaged apple detection with a hybrid YOLOv3 algorithm

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Information Processing in Agriculture 2024年第2期11卷 163-171页

作者： Meng Zhang Huazhao Liang Zhongju wang long wang Chao Huang Xiong Luo Schoolof Computer and Communication Engineering University of Science and Technoogy BejingBejing 1083China lShunde Innovation SchoolUniversity of Science and Technology BeijingFoshan 528399China

This paper proposes an improved You Only Look Once(YOLOv3)algorithm for automatically detecting damaged apples to promote the automation of the fruit processing *** the proposed method,a clustering method based on Rao-1 algorithm is introduced to optimize anchor box *** clustering method uses the intersection over the union to form the objective function and the most representative anchor boxes are generated for normal and damaged apple *** verify the feasibility and effectiveness of the proposed method,real apple images collected from the Internet are *** with the generic YOLOv3 and Fast Region-based Convolutional Neural Network(Fast R-CNN)algorithms,the proposed method yields the highest mean average precision value for the test ***,it is practical to apply the proposed method for intelligent apple detection and classification tasks.

关键词： Rao algorithm Apple detection Clustering Smart agriculture