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Enhancing cut selection through reinforcement learning

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Science China Mathematics 2024年第6期67卷 1377-1394页

作者： Shengchao Wang Liang chen.Lingfeng Niu yu-Hong dai Academy of Mathematics and Systems Science Chinese Academy of SciencesBeijing100190China Research Center on Fictitious Economy and Data Science Chinese Academy of SciencesBeijing100190China

With the rapid development of artificial intelligence in recent years,applying various learning techniques to solve mixed-integer linear programming(MILP)problems has emerged as a burgeoning research *** from constructing end-to-end models directly,integrating learning approaches with some modules in the traditional methods for solving MILPs is also a promising *** cutting plane method is one of the fundamental algorithms used in modern MILP solvers,and the selection of appropriate cuts from the candidate cuts subset is crucial for enhancing *** to the reliance on expert knowledge and problem-specific heuristics,classical cut selection methods are not always transferable and often limit the scalability and generalizability of the cutting plane *** provide a more efficient and generalizable strategy,we propose a reinforcement learning(RL)framework to enhance cut selection in the solving process of ***,we design feature vectors to incorporate the inherent properties of MILP and computational information from the solver and represent MILP instances as bipartite ***,we choose the weighted metrics to approximate the proximity of feasible solutions to the convex hull and utilize the learning method to determine the weights assigned to each ***,a graph convolutional neural network is adopted with a self-attention mechanism to predict the value of weighting ***,we transform the cut selection process into a Markov decision process and utilize RL method to train the *** experiments are conducted based on a leading open-source MILP solver *** on both general and specific datasets validate the effectiveness and efficiency of our proposed approach.

关键词： reinforcement learning mixed-integer linear programming cutting plane method cut selection

In-situ measurement via the flow-through method and numerical simulations for radon exhalation during measurements of the radon exhalation rate

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Nuclear Science and Techniques 2024年第7期35卷 192-207页

作者： Ming Xia Yong-Jun Ye Shan-Wei Shang Ting yu dai-Jia chen School of Resources Environment and Safety Engineering University of South ChinaHengyang421001China Key Discipline Laboratory for National Defense for Biotechnology in Uranium Mining and Hydrometallurgy University of South ChinaHengyang421001China

Small-scale measurements of the radon exhalation rate using the flow-through and closed-loop methods were conducted on the surface of a uranium tailing pond to better understand the differences between the two *** abnormal radon exhalation behavior was observed,leading to computational fluid dynamics(CFD)-based simulations in which dynamic radon migration in a porous medium and accumulation chamber was *** on the in-situ experimental and numerical simulation results,variations in the radon exhalation rate subject to permeability,flow rate,and insertion depth were quantified and *** in-situ radon exhalation rates measured using the flow-through method were higher than those measured using the closed-loop method,which could be explained by the negative pressure difference between the inside and outside of the chamber during the *** consistency of the variations in the radon exhalation rate between the experiments and simulations suggests the reliability of CFD-based techniques in obtaining the dynamic evolution of transient radon exhalation rates for diffusion and convection at the porous medium-air *** synergistic effects of the three factors(insertion depth,flow rate,and permeability)on the negative pressure difference and measured exhalation rate were quantified,and multivariate regression models were established,with positive correlations in most cases;the exhalation rate decreased with increasing insertion depth at a permeability of 1×10^(−11) m^(2).CFD-based simulations can provide theoretical guidance for improving the flow-through method and thus achieve accurate measurements.

关键词： Radon exhalation Flow-through Numerical simulation Accumulation chamber Multivariate regression

A novel algorithm for evaluating cement azimuthal density based on perturbation theory in horizontal well

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Petroleum Science 2024年第1期21卷 244-251页

作者： Ji-Lin Fan Feng Zhang Qian chen.Hao-chen.Song Lu-yu Zhong yue-Xiang dai National Key Laboratory of Deep Oil and Gas School of GeosciencesChina University of Petroleum(East China)Qingdao 266580ShandongChina China National Logging Corporation Xi'an 710076ShaanxiChina Sinopec Matrix Corporation Qingdao 266001ShandongChina

Cement density monitoring plays a vital role in evaluating the quality of cementing projects,which is of great significance to the development of oil and ***,the presence of inhomogeneous cement distribution and casing eccentricity in horizontal wells often complicates the accurate evaluation of cement azimuthal *** this regard,this paper proposes an algorithm to calculate the cement azimuthal density in horizontal wells using a multi-detector gamma-ray detection *** spatial dynamic response functions are simulated to obtain the influence of cement density on gamma-ray counts by the perturbation theory,and the contribution of cement density in six sectors to the gamma-ray recorded by different detectors is obtained by integrating the spatial dynamic response *** with the relationship between gamma-ray counts and cement density,a multi-parameter calculation equation system is established,and the regularized Newton iteration method is employed to invert casing eccentricity and cement azimuthal *** approach ensures the stability of the inversion process while simultaneously achieving an accuracy of 0.05 g/cm^(3) for the cement azimuthal *** accuracy level is ten times higher compared to density accuracy calculated using calibration ***,this algorithm enhances the accuracy of cement azimuthal density evaluation,provides valuable technical support for the monitoring of cement azimuthal density in the oil and gas industry.

关键词： Cement azimuthal density Perturbation theory Casing eccentricity Spatial dynamic response function Regularized Newton iteration

A hybrid physics-informed data-driven neural network for CO_(2) storage in depleted shale reservoirs

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Petroleum Science 2024年第1期21卷 286-301页

作者： Yan-Wei Wang Zhen-Xue dai Gui-Sheng Wang Li chen.yu-Zhou Xia yu-Hao Zhou College of Construction Engineering Jilin UniversityChangchun130026JilinChina Institute of Intelligent Simulation and Early Warning for Subsurface Environment Jilin UniversityChangchun130026JilinChina School of Energy Resources China University of GeosciencesBeijing100083China Department of Safety Environmental Protection and Quality ManagementShengli OilfieldSinopecDongying257000ShandongChina Key Laboratory of Thermo-Fluid Science and Engineering of MOE School of Energy and Power EngineeringXi'an Jiaotong UniversityXi'an710049ShaanxiChina College of Computer Science and Technology China University of Petroleum(East China)Qingdao266580ShandongChina Department of Physics University of FribourgFribourg1700Switzerland

To reduce CO_(2) emissions in response to global climate change,shale reservoirs could be ideal candidates for long-term carbon geo-sequestration involving multi-scale transport ***,most current CO_(2) sequestration models do not adequately consider multiple transport ***,the evaluation of CO_(2) storage processes usually involves laborious and time-consuming numerical simulations unsuitable for practical prediction and *** this paper,an integrated model involving gas diffusion,adsorption,dissolution,slip flow,and Darcy flow is proposed to accurately characterize CO_(2) storage in depleted shale reservoirs,supporting the establishment of a training *** this basis,a hybrid physics-informed data-driven neural network(HPDNN)is developed as a deep learning surrogate for prediction and *** incorporating multiple sources of scientific knowledge,the HPDNN can be configured with limited simulation resources,significantly accelerating the forward and inversion ***,the HPDNN can more intelligently predict injection performance,precisely perform reservoir parameter inversion,and reasonably evaluate the CO_(2) storage capacity under complicated *** validation and test results demonstrate that the HPDNN can ensure high accuracy and strong robustness across an extensive applicability range when dealing with field data with multiple noise *** study has tremendous potential to replace traditional modeling tools for predicting and making decisions about CO_(2) storage projects in depleted shale reservoirs.

关键词： Deep learning Physics-informed data-driven neural network Depleted shale reservoirs CO_(2)storage Transport mechanisms

Swelling behaviors of heterogeneous red-bed mudstone subjected to different vertical stresses

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第5期16卷 1847-1863页

作者： Kang Huang Zhangjun dai chen.zeng Yan Fei yu Wei Zhang Shanxiong chen State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil MechanicsChinese Academy of SciencesWuhan430071China University of Chinese Academy of Sciences Beijing100049China Faculty of Engineering China University of GeosciencesWuhanChina International Joint Research Center for Deep Earth Drilling and Resource Development China University of GeosciencesWuhan430074China

In this study,the axial swelling strain of red-bed mudstone under different vertical stresses are measured by swell-under-load method,and the microstructure of mudstone after hygroscopic swelling is studied by mercury intrusion porosimetry(MIP).The weakening coefficient and Weibull distribution function are introduced into the coupling model of mudstone moisture diffusion-swelling deformation-fracture based on finite-discrete element method(FDEM).The weakening effect of moisture on mudstone's mechanical parameters,as well as the heterogeneity of swelling deformation and stress distribution,is *** microcrack behavior and energy evolution of mudstone during hygroscopic swelling deformation under different vertical stresses are *** results show that the axial swelling strain of mudstone decreases with increase of the vertical *** low vertical stresses,moisture absorption in mudstone leads to formation of cracks caused by hydration-induced *** high vertical stresses,a muddy sealing zone forms on the mudstone surface,preventing further water *** simulation results of mudstone swelling deformation also demonstrate that it involves both swelling of the mudstone matrix and swelling caused by crack ***,crack expansion plays a dominant role in mudstone *** increasing vertical stress,the cracks in mudstone change from tensile cracks to shear cracks,resulting in a significant reduction in the total number of *** the evolution of mudstone kinetic energy shows similarities under different vertical stresses,the evolution of strain energy varies significantly due to the presence of different types of cracks in the *** findings provide a theoretical basis for understanding the hygroscopic swelling deformation mechanism of red-bed mudstone at various depths.

关键词： Heterogeneous red-bed mudstone Self-sealing band Matric swelling and crack expansion FDEM Microcracks Energy evolution

Influence of syngas components and ash particles on the radiative heat transfer in a radiant syngas cooler

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Chinese Journal of Chemical Engineering 2024年第4期68卷 203-215页

作者： chen.Han Youmin Situ Huaxing Zhu Jianliang Xu Zhenghua dai Guangsuo yu Haifeng Liu National Energy Coal Gasification Technology Research and Development Center East China University of Science and TechnologyShanghai 200237China Shanghai Engineering Research Center of Coal Gasification East China University of Science and TechnologyShanghai 200237China

Radiant syngas cooler(RSC)is widely used as a waste heat recovery equipment in industrial *** this work,an RSC with radiation screens is established and the impact of gaseous radiative property models,gas components,and ash particles on heat transfer is investigated by the numerical simulation *** the syngas components and the pressure environment of the RSC,a modified weighted-sum-of-gray-gases model was *** modified model shows high accuracy in *** computational fluid dynamics simulation,the calculated steam production is only 0.63%in error with the industrial *** with Smith's model,the temperature decay along the axial direction calculated by the modified model is *** components are of great significance to heat recovery capacity,especially when the absorbing gas fraction is less than 10%.After considering the influence of particles,the outlet temperature and the proportion of radiative heat transfer are less affected,but the difference in steam output reaches 2.7 t·h^(-1).The particle deposition on the wall greatly reduces the heat recovery performance of an RSC.

关键词： Radiant syngas cooler Weighted-sum-of-gray-gases model Numerical simulation Particle radiation

Ultrasmall copper-based clusterzymes ameliorate Achilles tendinopathy by inhibiting acute oxidative stress

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Nano Research 2024年第6期17卷 5374-5389页

作者： Xuzhuo chen.Yi Du Yazi Huang Xianhao Zhou Xinru Xie Chang Li chen.Zhao Fengrong dai Xijiao yu Shanyong Zhang Department of Oral Surgery Shanghai Ninth People’s HospitalShanghai Jiao Tong University School of MedicineCollege of StomatologyShanghai Jiao Tong UniversityNational Center for StomatologyNational Clinical Research Center for Oral DiseasesShanghai Key Laboratory of StomatologyShanghai Research Institute of StomatologyShanghai 200011China Department of Endodontics Central LaboratoryJinan Stomatological HospitalJinan Key Laboratory of Oral Tissue RegenerationShandong Provincial Health Commission Key Laboratory of Oral Diseases and Tissue RegenerationJinan 250001China State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China Department of Chemistry College of Chemistry and EnvironmentGuangdong Ocean UniversityZhanjiang 524088China Department of Orthopedics Shanghai Key Laboratory of Orthopedic ImplantShanghai Ninth People's HospitalShanghai Jiao Tong University School of MedicineShanghai 200011China

Tendinopathy is a prevalent musculoskeletal disorder,accounting for over 30%of musculoskeletal ***,current therapeutic strategies for tendinopathy are limited and often yield unsatisfactory clinical ***,there is a critical need to explore novel therapeutic approaches with minimal side effects for tendinopathy and its early *** this study,we successfully designed and synthesized a copper(I)-based nanocluster,named Cu_(11),which possesses remarkable enzyme-like and ROS-scavenging *** unique combination of properties qualifies Cu_(11)as an attractive anti-inflammatory and anti-ROS *** Cu_(11)clusterzymes specifically target mitochondria,effectively scavenging excessive reactive oxygen species(ROS)and reducing oxidative ***,Cu_(11)clusterzymes inhibit the activation of key signaling pathways involved in inflammation,namely tumor necrosis factor(TNF),mitogen-activated protein kinase(MAPK),and nuclear factor(NF)-κB,leading to a decrease in the release of proinflammatory ***,our in vivo experiments using a collagenase-induced acute Achilles tendinopathy model demonstrated that Cu_(11)clusterzymes effectively alleviate inflammation and oxidative stress,without causing systemic *** study highlights the potential of copper-based clusterzymes as therapeutic agents for the treatment of Achilles tendinopathy and other inflammatory *** unique enzyme-like and ROS-scavenging activities of Cu_(11)make it a promising candidate for further development and clinical translation.

关键词： nanoclusters clusterzymes oxidative stress tendinopathy reactive oxygen species(ROS)

Epidemiology of congenital diaphragmatic hernia among 24 million Chinese births:a hospital-based surveillance study

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World Journal of Pediatrics 2024年第7期20卷 712-722页

作者： Zhi-yu chen.Jing Tao Wen-Li Xu yu-Yang Gao Wen-Yan Li Zhen Liu Jia-yuan Zhou Li dai National Center for Birth Defects Monitoring West China Second University HospitalSichuan UniversityNo.17 Section 3 RenminnanluChengdu 610041China The Joint Laboratory for Pulmonary Development and Related Diseases West China Institute of Women and Children’s HealthWest China Second University HospitalSichuan UniversityChengduChina Key Laboratory of Birth Defects and Related Diseases of Women and Children Ministry of EducationSichuan UniversityChengduChina NHC Key Laboratory of Chronobology Sichuan UniversityChengduChina Med‑X Center for Informatics Sichuan UniversityChengduChina

Background The prevalence of congenital diaphragmatic hernia(CDH)varies across countries,with limited information available on its epidemiology in *** study aimed to investigate the prevalence,time trends,and perinatal outcomes of CDH in China,as well as its associated malformations and potential associations with maternal and infant *** This study included all birth and CDH cases from the Chinese Birth Defects Monitoring Network between 2007 and 2019,with CDH cases classified as either isolated or *** employed the joinpoint regression model to calculate the trends of prevalence and the annual percent change,with Poisson regression used for adjusted prevalence rate ratios.A P value≤0.05 was considered statistically *** A total of 4397 CDH cases were identified among 24,158,029 births in the study period,yielding prevalence rates of 1.82,1.13 and 0.69 per 10,000 for overall,isolated,and associated CDH,*** prevalence of each type of CDH increased over *** prevalence of overall CDH varied significantly by infant sex(male ***,1.91/10,000 vs.1.63/10,000),maternal residence(urban ***,2.13/10,000 vs.1.45/10,000),maternal age(<20 years,1.31/10,000;20-24 years,1.63/10,000;25-29 years,1.80/10,000;30-34 years,1.87/10,000;≥35 years,2.22/10,000),and geographic region(central,1.64/10,000;east,2.45/10,000;west,1.37/10,000).Cardiovascular anomalies were the most common malformations associated with *** with associated CDH had a higher risk of premature birth and perinatal death than those with isolated *** The increasing prevalence and high perinatal mortality rate of CDH highlight the need for further etiological,epidemiological,and clinical studies among the Chinese population.

关键词： China Congenital diaphragmatic hernia Epidemiology Prevalence

A Skin-Inspired Self-Adaptive System for Temperature Control During Dynamic Wound Healing

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Nano-Micro Letters 2024年第8期16卷 211-224页

作者： Yaqi Geng Guoyin chen.Ran Cao Hongmei dai Zexu Hu Senlong yu Le Wang Liping Zhu Hengxue Xiang Meifang Zhu State Key Laboratory for Modification of Chemical Fibers and Polymer Materials College of Materials Science and EngineeringDonghua University2999 North Renmin RoadShanghai 201620People’s Republic of China

The thermoregulating function of skin that is capable of maintaining body temperature within a thermostatic state is ***,patients suffering from skin damage are struggling with the surrounding scene and situational ***,we report an interactive self-regulation electronic system by mimicking the human thermos-reception *** skin-inspired self-adaptive system is composed of two highly sensitive thermistors(thermal-response composite materials),and a low-power temperature control unit(Laserinduced graphene array).The biomimetic skin can realize self-adjusting in the range of 35–42℃,which is around physiological *** thermoregulation system also contributed to skin barrier formation and wound *** wound models,the treatment group healed~10%more rapidly compared with the control group,and showed reduced inflammation,thus enhancing skin tissue *** skin-inspired self-adaptive system holds substantial promise for nextgeneration robotic and medical devices.

关键词： Thermo-reception Self-regulation Flexible electronic system Wound healing