检索结果-南通市图书馆

Numerical simulations for radon migration and exhalation behavior during measuring radon exhalation rate with closed-loop method

在线全文

学校读者我要写书评

暂无评论

Nuclear Science and Techniques 2024年第1期35卷 81-95页

作者： Ming Xia yong-Jun Ye Shu-yuan Liu School of Resources Environment and Safety Engineering University of South ChinaHengyang 421001China Key Discipline Laboratory for National Defense for Biotechnology in Uranium Mining and Hydrometallurgy University of South ChinaHengyang 421001China

Accurate measurements of the radon exhalation rate help identify and evaluate radon risk regions in the *** these measurement methods,the closed-loop method is frequently ***,traditional experiments are insufficient or cannot analyze the radon migration and exhalation patterns at the gas–solid interface in the accumulation *** CFD-based technique was applied to predict the radon concentration distribution in a limited space,allowing radon accumulation and exhalation inside the chamber intuitively and *** this study,three radon exhalation rates were defined,and two structural ventilation tubes were designed for the *** consistency of the simulated results with the variation in the radon exhalation rate in a previous experiment or analytical solution was *** effects of the vent tube structure and flow rate on the radon uniformity in the chamber;permeability,insertion depth,and flow rate on the radon exhalation rate and the effective diffusion coefficient on back-diffusion were *** on the results,increasing the inser-tion depth from 1 to 5 cm decreased the effective decay constant by 19.55%,whereas the curve-fitted radon exhalation rate decreased(lower than the initial value)as the deviation from the initial value increased by approximately 7%.Increasing the effective diffusion coefficient from 2.77×10^(-7) to 7.77×10^(-6) m^(2) s^(-1) made the deviation expand from 2.14 to 15.96%.The conclusion is that an increased insertion depth helps reduce leakage in the chamber,subject to notable back-diffusion,and that the closed-loop method is reasonably used for porous media with a low effective diffusion coefficient in view of the back-diffusion *** CFD-based simulation is expected to provide guidance for the optimization of the radon exhalation rate measurement method and,thus,the accurate measurement of the radon exhalation rate.

关键词： Radon exhalation Numerical simulation Accumulation chamber

Metarelation2vec:A Metapath-Free Scalable Representation Learning Model for Heterogeneous Networks

在线全文

学校读者我要写书评

暂无评论

Tsinghua Science and Technology 2024年第2期29卷 553-575页

作者： Lei Chen yuan Li yong Lei Xingye Deng School of Information and Electrical Engineering Hunan University of Science and TechnologyXiangtan 411201China School of Computer Science and Engineering Hunan University of Science and TechnologyXiangtan 411201China

Metapaths with specific complex semantics are critical to learning diverse semantic and structural information of heterogeneous networks(HNs)for most of the existing representation learning ***,any metapaths consisting of multiple,simple metarelations must be driven by domain *** sensitive,expensive,and limited metapaths severely reduce the flexibility and scalability of the existing models.A metapath-free,scalable representation learning model,called Metarelation2vec,is proposed for HNs with biased joint learning of all metarelations in a bid to address this ***,a metarelation-aware,biased walk strategy is first designed to obtain better training samples by using autogenerating cooperation probabilities for all metarelations rather than using expert-given ***,grouped nodes by the type,a common and shallow skip-gram model is used to separately learn structural proximity for each node ***,grouped links by the type,a novel and shallow model is used to separately learn the semantic proximity for each link ***,supervised by the cooperation probabilities of all meta-words,the biased training samples are thrown into the shallow models to jointly learn the structural and semantic information in the HNs,ensuring the accuracy and scalability of the *** experimental results on three tasks and four open datasets demonstrate the advantages of our proposed model.

关键词： metarelation random walk heterogeneous network metapath representation learning

A Deep Residual PLS for Data-Driven Quality Prediction Modeling in Industrial Process

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

IEEE/CAA Journal of Automatica Sinica 2024年第8期11卷 1777-1785页

作者： Xiaofeng yuan Weiwei Xu Yalin Wang Chunhua Yang Weihua gui School of Automation Central South UniversityChangsha 410083China She is now with Guangzhou Electromechanical Technician College Guangzhou 510000China

Partial least squares(PLS)model is the most typical data-driven method for quality-related industrial tasks like soft ***,only linear relations are captured between the input and output data in the *** is difficult to obtain the remaining nonlinear information in the residual subspaces,which may deteriorate the prediction performance in complex industrial *** fully utilize data information in PLS residual subspaces,a deep residual PLS(DRPLS)framework is proposed for quality prediction in this *** by deep learning,DRPLS is designed by stacking a number of PLSs successively,in which the input residuals of the previous PLS are used as the layer *** enhance representation,nonlinear function is applied to the input residuals before using them for stacking highlevel *** each PLS,the output parts are just the output residuals from its previous ***,the output prediction is obtained by adding the results of each *** effectiveness of the proposed DRPLS is validated on an industrial hydrocracking process.

关键词： Deep residual partial least squares(DRPLS) nonlinear function quality prediction soft sensor

Resource Allocation for Cognitive Network Slicing in PD-SCMA System Based on Two-Way Deep Reinforcement Learning

在线全文

学校读者我要写书评

暂无评论

China Communications 2024年第6期21卷 53-68页

作者： Zhang Zhenyu Zhang yong yuan Siyu Cheng Zhenjie School of Electronic Engineering Beijing University of Posts and TelecommunicationsBeijing 100876China Beijing Key Laboratory of Work Safety Intelligent Monitoring(Beijing University of Posts and Telecommunications) Beijing 100876China

In this paper,we propose the Two-way Deep Reinforcement Learning(DRL)-Based resource allocation algorithm,which solves the problem of resource allocation in the cognitive downlink network based on the underlay *** users(SUs)in the cognitive network are multiplexed by a new Power Domain Sparse Code Multiple Access(PD-SCMA)scheme,and the physical resources of the cognitive base station are virtualized into two types of slices:enhanced mobile broadband(eMBB)slice and ultrareliable low latency communication(URLLC)*** design the Double Deep Q Network(DDQN)network output the optimal codebook assignment scheme and simultaneously use the Deep Deterministic Policy Gradient(DDPG)network output the optimal power allocation *** objective is to jointly optimize the spectral efficiency of the system and the Quality of Service(QoS)of *** results show that the proposed algorithm outperforms the CNDDQN algorithm and modified JEERA algorithm in terms of spectral efficiency and QoS ***,compared with the Power Domain Non-orthogonal Multiple Access(PD-NOMA)slices and the Sparse Code Multiple Access(SCMA)slices,the PD-SCMA slices can dramatically enhance spectral efficiency and increase the number of accessible users.

关键词： cognitive radio deep reinforcement learning network slicing power-domain non-orthogonal multiple access resource allocation

SnO2/metal organic complex composite derived from low-temperature activated metal organic complex for advanced lithium storage

在线全文

学校读者我要写书评

暂无评论

Rare Metals 2024年第7期43卷 3032-3043页

作者： gui-Long Liu Zi-Han Zhao Jin-Ke Shen Zi-Bo Zhao Nai-Teng Wu Dong-Lei Guo Wei-Wei yuan yong Liu Ye-Hua Su Xian-Ming Liu Luoyang Key Laboratory of Green Energy Materials College of Chemistry and Chemical EngineeringLuoyang Normal University School of Materials Science and Engineering Henan University of Science and Technology Inner Mongolia Shijie Chemical Co. Ltd.

Sn-based metal organic complexes with coordination bonds,multi-active sites,and high theoretical capacity have attracted much attention as promising anodes for lithium ion ***,the low electrical conductivity and huge volume changes restricted their electrochemical stability and practical ***,Snbased anode with superior electrochemical performance,including a high reversible capacity of 1050.1 mAh·g-1at 2 A·g-1and a stable capacity of 1105.5 mAh·g-1after 500 cycles at 1 A·g-1,was fabricated via a low-temperature calcination strategy from Sn metal organic *** low-temperature calcination process regulates Sn-O bond and prevents the agglomeration of SnO2,generating highly dispersed SnO2decorated metal organic complexes and providing sufficient active sites for ion *** situ characterizations expound that the undecomposed Sn-based metal organic complexes could be transformed into SnO2during lithiation and delithiation,which enhances the electrical conductivity and induces a strong pseudo-capacitive behavior,accelerating the electrochemical kinetics;the multiple solid electrolyte interface with inflexible LiF and flexible ROCO2Li buffers the volume variation of the electrode,resulting in its high electrochemical *** work provides a simple strategy for preparing excellent Sn-based anodes from metal organic complexes and reveals the lithium storage mechanism of the prepared Snbased anode.

关键词： Metal organic complex Lithium ion battery Electrochemical activation Low-temperature activation Partial decomposition

Seismic responses of an intensively constructed metro station-passageway-shaft structure system

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Frontiers of Structural and Civil Engineering 2024年第5期18卷 760-775页

作者： Ruohan LI yong yuan Hong CHEN Xinxing LI Emilio BILOTTA Department of Geotechnical Engineering Tongji UniversityShanghai 200092China Department of Civil Architectural and Environmental EngineeringUniversity of Naples Federico IINaples 80125Italy State Key Laboratory of Disaster Reduction in Civil Engineering Tongji UniversityShanghai 200092China Shanghai Tunnel Engineering&Rail Transit Design and Research Institute Shanghai 200235China

Intensive construction methods offer benefits for metro station development,yet they present challenges for seismic design due to the spatially asymmetric configuration of passageway-shaft *** this study,a detailed numerical model of a station-passageway-shaft structure system built using intensive construction methods was developed and the deformation and damage modes under seismic loadings were *** results indicate that inconsistent deformation between the shaft and the station generates interaction through the connecting passageway,leading to damage near the opening of the station structure and both ends of the connecting passageway Damage is more severe under longitudinal *** with the opening plan that spans four segments,the opening plan that spans five segments exacerbates the overall degree of damage to the structure *** transverse excitation,the presence of interior structures intensifies the damage to the station and connecting passageway,while with such internal structure in place the impact is relatively minor under longitudinal *** with steel segments near the station opening can appreciably attenuate the *** contrast,introducing flexible joints at both ends of the connecting passageway intensifies the ***,reinforcement using steel segments emerges as an optimal seismic mitigation strategy.

关键词： earthquake intensive construction metro station numerical simulation

Recent advances in asymmetric synthesis with CO2

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Science China Chemistry 2020年第10期63卷 1336-1351页

作者： Chuan-Kun Ran Xiao-Wang Chen yong-yuan gui Jie Liu Lei Song Ke Ren Da-Gang Yu College of Chemistry and Materials Science Sichuan Normal UniversityChengdu 610068China Key Laboratory of Green Chemistry&Technology of Ministry of Education College of ChemistrySichuan UniversityChengdu 610064China

Carbon dioxide(CO2)is an important and appealing C1 building block in chemical synthesis due to its nontoxicity,abundance,availability and *** progress has been achieved in the chemical transformation of CO2 into high valueadded organic ***,the asymmetric synthesis with CO2 to form enantioenriched molecules,especially the catalytic process,has lagged far *** enantioselective incorporation of CO2 into organic compounds is highly desirable,as the corresponding chiral products,such as carboxylic acids and amino acids,are common structural units in a vast array of natural products and biologically active ***,we discuss recent progress toward the enantioselective incorporation of CO2 into organic molecules,which mainly rely on three strategies:1)kinetic resolution or desymmetrization of epoxides with CO2 to form chiral cyclic carbonates and polycarbonates;2)nucleophilic attack of O-or N-nucleophiles to CO2 in tandem with asymmetric C–O bond formation to prepare chiral cyclic carbonates and carbamates;3)direct enantioselective nucleophilic attack of organometallic reagents to CO2 with asymmetric C–C bond ***,challenges and future outlook in this area are also presented.

关键词： carbon dioxide asymmetric catalysis carbonate carbamate carboxylic acid

Investigating the Mechanism of Qu Du Qiang Fei 1 Hao Fang Formula against Coronavirus Disease 2019 Based on Network Pharmacology Method

在线全文

学校读者我要写书评

暂无评论

World Journal of Traditional Chinese Medicine 2024年第1期10卷 93-103页

作者： yuan-Hua Wang He-Yang Zhou Jin-Yun Ma gui-Qing Ding Hua Yu yong-Sheng Jin Xiao-Dong Cheng Institute of Clinical Immunology Yue-Yang Hospital of Integrative MedicineShanghai University of Traditional Chinese MedicineShanghaiChina School of Pharmacy Naval Medical UniversityShanghaiChina

Objective:Qu Du Qiang Fei 1 Hao Fang(QDQF1)is a novel Chinese herbal medicine formula used to treat coronavirus disease 2019(COVID-19).However,the pharmacological mechanisms of action of QDQF1 remain *** objective of this study was to identify the effective ingredients and biological targets of QDQF1 for COVID-19 *** and Methods:The effective ingredients and mechanisms of action of QDQF1 were analyzed by using network pharmacology methods,which included an analysis of the effective ingredients and corresponding targets,COVID-19-related target acquisition,compound-target network analyses,protein-protein interaction network analysis,Kyoto Encyclopedia of Genes and Genomes(KEGG)and Gene Ontology(GO)enrichment analyses,and molecular docking ***:In total,288 effective QDQF1 ingredients were *** identified 51 core targets from the 148 targets through an overlap between putative QDQF1 targets and COVID-19-related *** key components,including formononetin,kaempferol,luteolin,naringenin,quercetin,and wogonin were identified through component-target network *** functional enrichment analysis of the core targets revealed 1296 items,while KEGG pathway enrichment analysis identified 148 signaling *** central targets(CCL2,CXCL8,IL1B,IL6,MAPK1,MAPK3,MAPK8,STAT3,and TNF)related to the COVID-19 pathway were identified in the KEGG pathway enrichment ***,molecular docking analysis suggested that the docking scores of the six key components to the nine central targets were better than those to ***:QDQF1 may regulate multiple immune-and inflammation-related targets to inhibit the progression of severe acute respiratory syndrome coronavirus 2,and thus,may be suitable for the treatment of COVID-19.

关键词： Coronavirus disease 2019 molecular docking molecular mechanism network pharmacology Qu Du Qiang Fei 1 Hao Fang formula

Experimental and numerical study of hypervelocity impact damage on composite overwrapped pressure vessels

在线全文

学校读者我要写书评

暂无评论

Defence Technology（防务技术） 2024年第1期31卷 58-72页

作者： yong-Pan Duan Run-Qiang Chi Bao-Jun Pang yuan Cai Hypervelocity Impact Research Center Harbin Institute of TechnologyHarbin150080China College of Science Heilongjiang University of Science and TechnologyHarbin 150022China

Ground-based tests are important for studying hypervelocity impact(HVI)damage to spacecraft pressure vessels in the orbital debris *** analyzed the damage to composite overwrapped pressure vessels(COPVs)in the HVI tests and classified the damage into non-catastrophic damage and catastrophic *** proposed a numerical simulation method to further study non-catastrophic damage and revealed the characteristics and mechanisms of non-catastrophic damage affected by impact conditions and internal *** fragments of the catastrophically damaged COPVs were collected after the *** crack distribution and propagation process of the catastrophic ruptures of the COPVs were *** findings contribute to understanding the damage characteristics and mechanisms of COPVs by HVIs.

关键词： Orbital debris Hypervelocity impact Composite overwrapped pressure vessels Damage mechanisms