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Computer Modeling in Engineering & Sciences 2024年第9期140卷 2559-2586页

作者： Tengda Li gang Wang Qiang fu College of Air and Missile Defense Air Force Engineering UniversityXi’an710051China

Aiming at the problems of low solution accuracy and high decision pressure when facing large-scale dynamic task allocation(DTA)and high-dimensional decision space with single agent,this paper combines the deep reinforce-ment learning(DRL)theory and an improved Multi-Agent Deep Deterministic Policy Gradient(MADDPG-D2)algorithm with a dual experience replay pool and a dual noise based on multi-agent architecture is proposed to improve the efficiency of *** algorithm is based on the traditional Multi-Agent Deep Deterministic Policy Gradient(MADDPG)algorithm,and considers the introduction of a double noise mechanism to increase the action exploration space in the early stage of the algorithm,and the introduction of a double experience pool to improve the data utilization rate;at the same time,in order to accelerate the training speed and efficiency of the agents,and to solve the cold-start problem of the training,the a priori knowledge technology is applied to the training of the ***,the MADDPG-D2 algorithm is compared and analyzed based on the digital battlefield of ground and air *** experimental results show that the agents trained by the MADDPG-D2 algorithm have higher win rates and average rewards,can utilize the resources more reasonably,and better solve the problem of the traditional single agent algorithms facing the difficulty of solving the problem in the high-dimensional decision *** MADDPG-D2 algorithm based on multi-agent architecture proposed in this paper has certain superiority and rationality in DTA.

关键词： Deep reinforcement learning dynamic task allocation intelligent decision-making multi-agent system MADDPG-D2 algorithm

Metal-to-insulator transition in platinum group compounds

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Rare Metals 2024年第8期43卷 3460-3474页

作者： Yu-Xuan Xia Jian-gang He Nuo-fu Chen Ji-Kun Chen School of New Energy North China Electric Power UniversityBeijing102206China School of Mathematics and Physics University of Science and Technology BeijingBeijing 100083China Key Laboratory of Advanced Materials and Devices for PostMoore Chips(Ministry of Education) School of Materials Science and EngineeringJniversity of Science and Technology BeijingBeijing 100083China

The metal-to-insulator transition(MIT) as usually achieved in 3d-orbital transitional metal(TM) compounds opens up a new paradigm in correlated electronics via triggering abrupt variations in their transportation *** to such 3d-orbital TM compounds,the MIT within the platinum group(Pg) element compounds based on the 4d-and 5d-orbital configurations is more complicated,owing to their elevation in the spinorbit coupling and meanwhile weakened intra-atomic Coulomb *** brings in a new freedom to regulate the balance in their metallic or semiconductive orbital configurations,while their MIT properties can be potentially combined with their spintronic properties to enable new electronic ***,we review the electronic transport and MIT behaviors within the existing family of Pg-containing compounds,particularly those showing first-order MIT behaviors that can be useful in correlated *** is also hoped that summarizing the presently reported Pg-containing MIT compounds will lead to the discovery of more new material families and/or new mechanisms associated with the Pg-containing compounds showing MIT properties.

关键词： Metal-to-insulator transition Platinum group compounds Electron correlation Spin-orbital coupling

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

Differences and identification on multi-time hydrocarbon generation of carboniferous-permian coaly source rocks in the Huanghua Depression,Bohai Bay Basin

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Petroleum Science 2024年第2期21卷 765-776页

作者： jin-Jun Xu Xian-gang Cheng Shu-Nan Peng Jun-Cai Jiang Qi-Long Wu Da Lou fu-Qi Cheng La-Mei Lin National Key Laboratory of Deep Oil and Gas China University of Petroleum(East China)Qingdao 266580ShandongChina PetroChina Dagang Oilfield Company Tianjin300280China

Coal is a solid combustible mineral,and coal-bearing strata have important hydrocarbon generation potential and contribute to more than 12%of the global hydrocarbon ***,the deposition and hydrocarbon evolution process of ancient coal-bearing strata is characterized by multiple geological times,leading to obvious distinctions in their hydrocarbon generation potential,geological processes,and production,which affect the evaluation and exploration of hydrocarbon resources derived from coaly source rocks *** study aimed to identify the differences on oil-generated parent macerals and the production of oil generated from different coaly source rocks and through different oil generation *** with the analysis of previous tectonic burial history and hydrocarbon generation history,high-temperature and high-pressure thermal simulation experiments,organic geochemistry,and organic petrology were performed on the Carboniferous-Permian(C-P)coaly source rocks in the Huanghua Depression,Bohai Bay *** oil-generated parent macerals of coal's secondary oil generation process(SOGP)were mainly hydrogen-rich collotelinite,collodetrinite,sporinite,and cutinite,while the oil-generated parent macerals of tertiary oil generation process(TOGP)were the remaining small amount of hydrogen-rich collotelinite,sporinite,and cutinite,as well as dispersed soluble organic matter and unexhausted residual *** with coal,the oil-generated parent macerals of coaly shale SOGP were mostly sporinite and *** part of hydrogen-poor vitrinite,lacking hydrocarbon-rich macerals,and macerals of the TOGP,in addition to some remaining cutinite and a small amount of crude oil and bitumen from SOGP contributed to the oil *** results indicated that the changes in oil yield had a good junction between SOGP and TOGP,both coal and coaly shale had higher SOGP aborted oil yield than TOGP starting yield,and coaly shale TOGP peak oil yield was low

关键词： Thermal simulation Multi-time oil generation processes Coaly source rock Carboniferous-permian Huanghua Depression

Ablation behaviour and mechanical performance of ZrB_(2)-ZrC-SiC modified carbon/carbon composites prepared by vacuum infiltration combined with reactive melt infiltration

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新型炭材料（中英文） 2024年第4期39卷 633-644页

作者： ZHANG Jia-ping SU Xiao-xuan LI Xin-gang WANG Run-ning fu Qian-gang Shaanxi Key Laboratory of Fiber Reinforced Light Composite Materials Northwestern Polytechnical UniversityXi’an 710072China

The development of advanced aircraft relies on high performance thermal-structural materials,and carbon/carbon com-posites(C/C)composited with ultrahigh-temperature ceramics are ideal ***,the traditional routes of compositing are either inefficient and expensive or lead to a non-uniform distribution of ceramics in the *** with the traditional C/C-ZrC-SiC composites prepared by the reactive melt infiltration of ZrSi_(2),C/C-ZrB_(2)-ZrC-SiC composites prepared by the vacuum infiltration of ZrB_(2) combined with reactive melt infiltration have the higher content and more uniform distribution of the introduced ceramic *** mass and linear ablation rates of the C/C-ZrB_(2)-ZrC-SiC composites were respectively 68.9%and 29.7%lower than those of C/C-ZrC-SiC composites prepared by reactive melt *** ablation performance was improved because the volatilization of B_(2)O_(3),removes some of the heat,and the more uniformly distributed ZrO_(2),that helps produce a ZrO2-SiO2 continu-ous protective layer,hinders oxygen infiltration and decreases ablation.

关键词： C/C composites ZrB_(2)-ZrC-SiC Vacuum filtration Reactive melt infiltration Ablation.

Temperature field characteristics of CF/PEEK thermoplastic composites formed by automated fiber placement using hot gas torch with slit structure nozzle

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Chinese Journal of Aeronautics 2024年第6期37卷 392-409页

作者： Ziang jin Shouzheng SUN Sunil Chandrakant JOSHI Zhenyu HAN Hongya fu State Key Laboratory of Robotics and System Harbin Institute of TechnologyHarbin 150001China School of Mechanical and Aerospace Engineering Nanyang Technological UniversitySingapore 639798Singapore

In-situ consolidation forming of high-performance thermoplastic composites by Automated Fiber Placement(AFP)is of significant interest in *** the laying process,the heating temperature has a great influence on the quality of the formed components.A threedimensional heat transfer finite element model of Carbon Fiber(CF)/Polyether Ether Ketone(PEEK)heated by Slit Structure Nozzle Hot Gas Torch(SSNHGT)assisted AFP is *** influence of gas flow rate,heat transfer distance,and laying speed on heating temperature is *** results show that the overall temperature increases and then decreases as the gas flow rate *** the increase in heat transfer distance and laying speed,the overall temperature ***,the gas flow rate has the greatest influence on the temperature of CF/PEEK being heated,followed by the laying speed and finally the heat transfer ***,the model can also be extended to other fiber-reinforced polymer composites formed by hot gas torch assisted AFP,which can guide the optimization of process parameters for subsequent heating temperature control.

关键词： Fiber reinforced plastics Thermoplastics Heating temperature Automated fiber placement CF/PEEK

Solid particle size characterization by a high-frequency collision response in pneumatic particulate flow

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Particuology 2024年第3期86卷 39-54页

作者： Kai Wang Yichen Li Ziang Chang Min Qin Guangming fu Bangtang Yin gang Wang jiaqi Tian School of Petroleum Engineering China University of Petroleum(East China)Qingdao266580China Key Laboratory of Unconventional Oil&Gas Development China University of Petroleum(East China)Ministry of EducationQingdao266580China National Engineering Research Center of Oil&Gas Drilling and Completion Technology Qingdao266580China Shock and Vibration of Engineering Materials and Structures Key Lab ofSichuan Province Southwest University of Science and TechnologyMianyang621000China

A novel triaxial vibration method is developed for the real-time characterization of the solid particle size distribution(PsD)in pneumatic particulate flow,which is critical for chemical *** this work,the particle-wall collision and friction behaviours were analysed by the time-domain statistical and timefrequency joint methods to narrow the high-frequency response range by the initial experiment of free fall for a single particle,interparticle,and multiple ***,verification experiments of PSD characterization in pneumatic flow were ***,the quantitative triaxial energy response model that considers the particle size,shape,and mass factors were ***,a good agreement of the particle number identification was found between the triaxial vibration energy and mean particle size of 150-550μ***,the performance with the best accuracy was focused on a range of 42-43 kHz in the x-axis and z-axis and 36.8-38.8 kHz in the ***,the individual particle energy was inversely analysed by the triaxial vibration response within the optimized frequency bands,and the PSD was characterized in real-time by a low error rate,that is,5.2% from the XZ-axis direction of sand(42-43 kHz)and 5.6% from the XYZ-axis of glass(30.9-33.9 kHz,46.2-47.2 kHz,38.3-41.3 kHz for each axis response).Therefore,this research complements the existing approaches for PsD characterization in particulate multiphase flow.

关键词： Solid particulate flow Triaxial vibration High-frequency response Particle wall Particle size distribution

Tight gas production model considering TPG as a function of pore pressure,permeability and water saturation

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Petroleum Science 2020年第5期17卷 1356-1369页

作者： Atif Zafar Yu-Liang Su Lei Li jin-gang fu Asif Mehmood Wei-Ping Ouyang Mian Zhang School of Petroleum Engineering China University of Petroleum(East China)Qingdao 266580ShandongChina Department of Petroleum Technology University of KarachiUniversity RoadKarachi 75270Pakistan Changqing Downhole Technology Company Chuangqing Drilling Engineering Co.LtdCNPCXi’an 710018ShaanxiChina

Threshold pressure gradient has great importance in efficient tight gas field development as well as for research and laboratory *** experimental study is carried out to investigate the threshold pressure gradient in *** are carried out with and without back pressure so that the effect of pore pressure on threshold pressure gradient may be *** trend of increasing or decreasing the threshold pressure gradient is totally opposite in the cases of considering and not considering the pore *** results demonstrate that the pore pressure of tight gas reservoirs has great influence on threshold pressure *** effects of other parameters like permeability and water saturation,in the presence of pore pressure,on threshold pressure gradient are also examined which show that the threshold pressure gradient increases with either a decrease in permeability or an increase in water *** new correlations of threshold pressure gradient on the basis of pore pressure and permeability,and pore pressure and water saturation,are also *** on these equations,new models for tight gas production are *** gas slip correction factor is also considered during derivation of this proposed tight gas production *** performance relationship curves based on these proposed models show that production rates and absolute open flow potential are always be overestimated while ignoring the threshold pressure gradients.

关键词： Inflow performance relationship Pore pressure Threshold pressure gradient Tight gas field development Tight gas sand reservoir

The effect of fasting plasma glucose on in-hospital mortality after acute myocardial infarction in patients with and without diabetes:findings from a prospective,nationwide,and multicenter registry

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Journal of Geriatric Cardiology 2024年第5期21卷 523-533页

作者： Rui fu Ying-Xuan ZHU Kong-Yong CUI jin-gang YANG Hai-Yan XU Dong YIN Wei-Hua SONG Hong-Jian WANG Cheng-gang ZHU Lei FENG Wei WU Kai-HongCHEN Yan-Yan ZHAO Ye LU Ke-Fei DOU Yue-jin YANG on behalf of the CAMI Registry Investigators Cardiometabolic Medicine Center Fuwai HospitalNational Center for Cardiovascular DiseasesState Key Laboratory of Cardiovascular DiseaseNational Clinical Research Center for Cardiovascular DiseasesChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingChina Medical Research&Biometrics Center Fuwai HospitalNational Center for Cardiovascular DiseasesChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingChina Coronary Heart Disease Center Fuwai HospitalNational Center for Cardiovascular DiseasesState Key Laboratory of Cardiovascular DiseaseNational Clinical Research Center for Cardiovascular DiseasesChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingChina Department of Cardiology Guangzhou Traditional Chinese Medical College First Affiliated HospitalGuangdong ProvinceChina Department of Cardiology Longyan Hospital First HospitalFujian ProvinceChina 不详

OBJECTIVES To evaluate the predictive value of fasting plasma glucose(FPG)for in-hospital mortality in patients with acute myocardial infarction(AMI)with different glucose metabolism *** We selected 5,308 participants with AMI from the prospective,nationwide,multicenter CAMI registry,of which 2,081 were diabetic and 3,227 were *** were divided into high FPG and low FPG groups according to the optim-al cutoff values of FPG to predict in-hospital mortality for diabetic and nondiabetic cohorts,*** primary endpoint was in-hospital *** Overall,94 diabetic patients(4.5%)and 131 nondiabetic patients(4.1%)died during hospitalization,and the optimal FPG thresholds for predicting in-hospital death of the two cohorts were 13.2 mmol/L and 6.4 mmol/L,*** with individuals who had low FPG,those with high FPG were significantly associated with higher in-hospital mortality in diabet-ic cohort(10.1%vs.2.8%;odds ratio[OR]=3.862,95%confidence interval[CI]:2.542-5.869)and nondiabetic cohort(7.4%vs.1.7%;HR=4.542,95%CI:3.041-6.782).After adjusting the potential confounders,this significant association was not ***-more,FPG as a continuous variable was positively associated with in-hospital mortality in single-variable and multivariable models regardless of diabetic *** FPG to the original model showed a significant improvement in C-statistic and net reclassification in diabetic and nondiabetic *** This large-scale registry indicated that there is a strong positive association between FPG and in-hospital mor-tality in AMI patients with and without *** might be useful to stratify patients with AMI.

关键词： patients fasting infarction

Housing vacancy identification in shrinking cities based on multi-source data:A case study of fushun city in Northeast China

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Journal of Geographical Sciences 2024年第1期34卷 89-111页

作者： SUN Hongri ZHOU Guolei LIU Yanjun fu Hui jin Yu School of Geographical Sciences Northeast Normal UniversityChangchun 130024China Northeast Institute of Geography and Agroecology CASChangchun 130102China

Urban shrinkage has attracted the attention of many geographers and urban planners in recent ***,there are fewer studies on vacant housing in shrinking ***,this study combines multi-source remote sensing images and urban building data to assess the spatiotemporal variation patterns of housing vacancy in a typical shrinking city in *** following points were obtained:(1)We developed an evaluation model to identify vacant residential buildings in shrinking cities by removing the contribution of nighttime lights from roads and non-residential buildings;(2)The residential building vacancy rate in fushun city significantly increased from 2013 to 2020,resulting in a significant high-value clustering *** impact of urban shrinkage on vacant residential buildings was higher than that on vacant non-residential buildings;(3)The World Pop population data demonstrated consistent spatial distribution and trend of population change in fushun with the residential building vacancy rate results,suggesting good reliability of the constructed evaluation model in this *** housing vacancies can help the local government to raise awareness of the housing vacancy problem in shrinking cities and to propose reasonable renewal strategies.

关键词： housing vacancy residential building vacancy urban shrinkage VIIRS