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Fluid Dynamics & Materials Processing 2022年第6期18卷 1699-1709页

作者： Xufeng li yantao Bi Shengli Petroleum Engineering Co. Ltd.of SinopecDongying257100China Key Laboratory of Ultra-Deep Well Drilling Engineering Technology of Sinopec Dongying257100China Key Laboratory of Unconventional Drilling and Completion Technology of China Petroleum and Chemical Corporation Dongying257100China

Using the conservation equations for mass,momentum and energy,a model is elaborated to describe the dynamics of high-energy gases in composite-perforation technological processes.The model includes a precise representation of the gunpowder combustion and related killing fluid displacement.Through numerical solution of such equations,the pressure distribution of the high-energy gas in fractures is obtained,and used to determine crack propagation.The accuracy of the model is verified by comparing the simulation results with actual measurements.

关键词： Composite perforation gunpowder burning pressure distribution downhole pressure

A distributed EEMDN-SABiGRU model on Spark for passenger hotspot prediction

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信息与电子工程前沿:英文版 2023年第9期24卷 1316-1331页

作者： Dawen XIA Jian GENG Ruixi HUANG Bingqi SHEN Yang HU Yantao LI Huaqing li College of Data Science and Information Engineering Guizhou Minzu UniversityGuiyang 550025China Department of Automotive Engineering Guizhou Traffic Technician and Transportation CollegeGuiyang 550008China College of Computer Science Chongqing UniversityChongqing 400044China College of Electronic and Information Engineering Southwest UniversityChongqing 400715China

To address the imbalance problem between supply and demand for taxis and passengers,this paper proposes a distributed ensemble empirical mode decomposition with normalization of spatial attention mechanism based bi-directional gated recurrent unit(EEMDN-SABiGRU)model on Spark for accurate passenger hotspot prediction.It focuses on reducing blind cruising costs,improving carrying efficiency,and maximizing incomes.Specifically,the EEMDN method is put forward to process the passenger hotspot data in the grid to solve the problems of non-smooth sequences and the degradation of prediction accuracy caused by excessive numerical differences,while dealing with the eigenmodal EMD.Next,a spatial attention mechanism is constructed to capture the characteristics of passenger hotspots in each grid,taking passenger boarding and alighting hotspots as weights and emphasizing the spatial regularity of passengers in the grid.Furthermore,the bi-directional GRU algorithm is merged to deal with the problem that GRU can obtain only the forward information but ignores the backward information,to improve the accuracy of feature extraction.Finally,the accurate prediction of passenger hotspots is achieved based on the EEMDN-SABiGRU model using real-world taxi GPS trajectory data in the Spark parallel computing framework.The experimental results demonstrate that based on the four datasets in the 00-grid,compared with LSTM,EMDLSTM,EEMD-LSTM,GRU,EMD-GRU,EEMD-GRU,EMDN-GRU,CNN,and BP,the mean absolute percentage error,mean absolute error,root mean square error,and maximum error values of EEMDN-SABiGRU decrease by at least 43.18%,44.91%,55.04%,and 39.33%,respectively.

关键词： Passenger hotspot prediction Ensemble empirical mode decomposition(EEMD) Spatial attention mechanism Bi-directional gated recurrent unit(BiGRU) GPS trajectory Spark

APFD:an effective approach to taxi route recommendation with mobile trajectory big data

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Frontiers of Information Technology & Electronic Engineering 2022年第10期23卷 1494-1510页

作者： Wenyong ZHANG Dawen XIA Guoyan CHANG Yang HU Yujia HUO Fujian FENG Yantao LI Huaqing li College of Data Science and Information Engineering Guizhou Minzu UniversityGuiyang 550025China Department of Automotive Engineering Guizhou Traffic Technician and Transportation CollegeGuiyang 550008China College of Computer Science Chongqing UniversityChongqing 400044China College of Electronic and Information Engineering Southwest UniversityChongqing 400715China The Affiliated Hospital of Guizhou Medical University Guiyang 550001China

With the rapid development of data-driven intelligent transportation systems,an efficient route recommendation method for taxis has become a hot topic in smart cities.We present an effective taxi route recommendation approach(called APFD)based on the artificial potential field(APF)method and Dijkstra method with mobile trajectory big data.Specifically,to improve the efficiency of route recommendation,we propose a region extraction method that searches for a region including the optimal route through the origin and destination coordinates.Then,based on the APF method,we put forward an effective approach for removing redundant nodes.Finally,we employ the Dijkstra method to determine the optimal route recommendation.In particular,the APFD approach is applied to a simulation map and the real-world road network on the Fourth Ring Road in Beijing.On the map,we randomly select 20 pairs of origin and destination coordinates and use APFD with the ant colony(AC)algorithm,greedy algorithm(A*),APF,rapid-exploration random tree(RRT),non-dominated sorting genetic algorithm-II(NSGA-II),particle swarm optimization(PSO),and Dijkstra for the shortest route recommendation.Compared with AC,A*,APF,RRT,NSGA-II,and PSO,concerning shortest route planning,APFD improves route planning capability by 1.45%–39.56%,4.64%–54.75%,8.59%–37.25%,5.06%–45.34%,0.94%–20.40%,and 2.43%–38.31%,respectively.Compared with Dijkstra,the performance of APFD is improved by 1.03–27.75 times in terms of the execution efficiency.In addition,in the real-world road network,on the Fourth Ring Road in Beijing,the ability of APFD to recommend the shortest route is better than those of AC,A*,APF,RRT,NSGA-II,and PSO,and the execution efficiency of APFD is higher than that of the Dijkstra method.

关键词： Big data analytics Region extraction Artificial potential field Dijkstra Route recommendation GPS trajectories of taxis

（G, s）-Transitive Graphs of Valency 7

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Algebra Colloquium 2016年第3期23卷 493-500页

作者： Songtao Guo Yantao LI Xiaohui Hua School of Mathematics and Statistics Henan University of Science and Technology Luoyang Henan 471023 China College of Arts and Science Beijing Union University Beijing 100091 China College of Mathematics and Information Science Henan Normal University Xinxiang Henan 453007 China

Let X be a finite simple undirected graph and G an automorphism group of X. If G is transitive on s-arcs but not on （s ＋ 1）-arcs then X is called （G, s）-transitive. Let X be a connected （G, s）-transitive graph of a prime valency p, and Gv the vertex stabilizer of a vertex v E V（X） in G. For the case p = 3, the exact structure of Gv has been determined by Djokovid and Miller in [Regular groups of automorphisms of cubic graphs, J. Combin. Theory （Ser. B） 29 （1980） 195-230]. For the case p = 5, all the possibilities of Gv have been given by Guo and Feng in [A note on pentavalent s-transitive graphs, Discrete Math. 312 （2012） 2214-2216]. In this paper, we deal with the case p = 7 and determine the exact structure of the vertex stabilizer Gv.

关键词： symmetric graph s-transitive graph （G s）-transitive graph

Damage assessment and diagnosis of hydraulic concrete structures using optimization-based machine learning technology

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Frontiers of Structural and Civil Engineering 2023年第8期17卷 1281-1294页

作者： yantao ZHU Qiangqiang JIA Kang ZHANG Yangtao li Zhipeng li Haoran WANG State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Hohai UniversityNanjing 210098China College of Water Conservancy and Hydropower Engineering Hohai UniversityNanjing 210098China National Dam Safety Research Center Wuhan 430010China Changjiang Institute of Survey PlanningDesignand ResearchWuhan 430010China

Concrete is widely used in various large construction projects owing to its high durability,compressive strength,and plasticity.However,the tensile strength of concrete is low,and concrete cracks easily.Changes in the concrete structure will result in changes in parameters such as the frequency mode and curvature mode,which allows one to effectively locate and evaluate structural damages.In this study,the characteristics of the curvature modes in concrete structures are analyzed and a method to obtain the curvature modes based on the strain and displacement modes is proposed.Subsequently,various indices for the damage diagnosis of concrete structures based on the curvature mode are introduced.A damage assessment method for concrete structures is established using an artificial bee colony backpropagation neural network algorithm.The proposed damage assessment method for dam concrete structures comprises various modal parameters,such as curvature and frequency.The feasibility and accuracy of the model are evaluated based on a case study of a concrete gravity dam.The results show that the damage assessment model can accurately evaluate the damage degree of concrete structures with a maximum error of less than 2%,which is within the required accuracy range of damage identification and assessment for most concrete structures.

关键词： hydraulic structure curvature mode damage detection artifical neural network artificial bee colony

Cu_(3)P@Ni core-shell heterostructure with modulated electronic structure for highly efficient hydrogen evolution

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Nano Research 2022年第4期15卷 2935-2942页

作者： Jiayi Chen Xu li Bo Ma Xudong Zhao yantao Chen Tianjin Key Lab for Photoelectric Materials and Devices School of Materials Science and EngineeringTianjin University of TechnologyTianjin 300384China Key Laboratory of Advanced Energy Materials Chemistry(Ministry of Education) College of ChemistryNankai UniversityTianjin 300071China

The sluggish charge transfer and poor intrinsic activity are the bottlenecks that hamper the further development of electrocatalysts for hydrogen evolution.A novel core-shell heterostructure of Cu_(3)P@Ni is fabricated,which is composed of Cu_(3)P nanorods covered by metallic Ni.The as-prepared Cu_(3)P@Ni exhibits a durable and superior activity toward hydrogen evolution,with an overpotential of 42 mV to deliver 10 mA·cm^(-2)and a Tafel slope of 41 mV·dec^(-1).Charge redistribution is observed after successfully constructing the core-shell heterostructure,leading to the altered electronic structure.The theoretical calculations have manifested that Cu_(3)P@Ni exhibits a zero bandgap and optimized adsorption strength of intermediates,which could give rise to the accelerated charge transfer as well as increased intrinsic activity.This work could shed light on the development of novel electrocatalysts with modulated electronic structure for highly efficient hydrogen evolution.

关键词： heterostructure electronic structure hydrogen evolution reaction electrocatalyst

Responses in splanchnic and mammary amino acid metabolism to short-term graded removal of methionine in lactating goats

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Animal Nutrition 2023年第2期13卷 116-125页

作者： Yantao LI Mark D.Hanigan Xueyan lin Zhiyong Hu Zhengui Yan Qiuling Hou Yun Wang Zhonghua Wang Ruminant Nutrition and Physiology Laboratory College of Animal Science and TechnologyShandong Agricultural UniversityTai'an 271018China Department of Dairy Science Virginia TechBlacksburg 24061USA

Four multi-catheterized lactating goats were used in a 4×4 Latin square experiment to investigate the responses of amino acid metabolism in portal-drained viscera(PDV),liver,and mammary glands to short-term varying supplies of methionine(Met).During the last 45 h in each experimental period,goats were fasted for 12 h and then abomasally infused with an amino acid(AA)mixture plus glucose for 33 h.Treatments consisted of graded removal of Met from an infused AA mixture to achieve Met content in the infusate of 100%(complete),60%,30%,or 0%that in casein.Graded Met removal decreased the pro-duction of milk,milk protein,lactose,and fat linearly whilst also decreasing arterial Met concentration linearly(Pliver removal of Met decreased linearly(Pliver(P0.1)was maintained as Met supply declined.This was achieved through increased mammary affinity(Plinearly decreased mammary uptake-to-milk output ratios of Met(Plinearly(0.05linearly decreased circulating concentration of prolactin and linearly increased insulin concentration(Plism of Met in PDV,liver,and peripheral tissue(including mammary glands)and a linear increase in mammary blood flow.The observed decreases in milk protein production as Met supply decreased appear to be a result of regulatory events which may have been driven by decreased circulating prolactin,rather than as a result of decreased mammary Met uptake.

关键词： Methionine Lactating goat Milk protein Amino acid Splanchnic tissue

Chloride-binding capacity of mortars composed of marine sand subjected to external chloride penetration

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Journal of Oceanology and limnology 2022年第4期40卷 1462-1471页

作者： Congtao SUN Ming SUN Tao TAO Feng QU Gongxun WANG Peng ZHANG Yantao LI Jizhou DUAN Key Laboratory of Marine Environmental Corrosion and Bio-fouling Institute of OceanologyChinese Academy of SciencesQingdao 266071China School of Civil Engineering Qingdao University of TechnologyQingdao 266033China School of Civil Engineering Hunan University of Science and TechnologyXiangtan 411201China Open Studio for Marine Corrosion and Protection Pilot National Laboratory for Marine Science and Technology(Qingdao)Qingdao 266237China Nantong Research and Development Center of Marine Science and Technology Institute of OceanologyChinese Academy of SciencesNantong 226004China

In order to explore the interactional relations of internal chloride and external chloride-binding amongst the cementitious materials,the chloride-binding capacity of mortars composed of marine sand(MS)or washed marine sand(WMS)were investigated.Results indicate that more external chloride can penetrate and diff use more deeply into the WMS mortar than that in the MS mortar.This phenomenon suggests that the external chloride migration resistance due to WMS is lower than that caused by MS.The distribution trends of the bound chloride content in the two types of mortars are the same at diff erent immersion times.However,a signifi cantly decreased area of the bound chloride content exists at the border of the external penetration area(EPA)and the external unaff ected area(EUA)at the immersion ages of 3 and 7 d,and then it disappears gradually with immersion time.The WMS mortar can bind more external chloride,whereas the MS mortar can bind more internal chloride,at diff erent immersion times.The distributions of bound chloride conversion rate in the EPAs of the two types of mortars diff er across immersion times.The distribution fi rstly decreases,and then it increases at the immersion ages of 3 and 7 d.The distribution was from increase,then decreases,and increase again at the immersion ages of 28 and 56 d.The bound chloride conversion rate in the WMS mortar is aff ected more greatly by external chloride penetration than that in the MS mortar.The amounts of the Friedel’s salt tend to increase with prolonged immersion time.Finally,the penetration of external chloride can increase the amount of fi ne capillary pores smaller than 100 nm in the WMSmortar exposed for 56 d in the chloride salt solution(WMS-E)specimen.

关键词： marine sand mortar chloride binding Friedel’s salt pore structure

Inductive eff ect of bioactive substances on strobilation of jellyfi sh Aurelia coerulea

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Journal of Oceanology and limnology 2020年第5期38卷 1548-1558页

作者： WANG Nan WANG Minxiao WANG yantao li Chaolun Key Laboratory of Marine Ecology and Environmental Sciences Center of Deep-sea ResearchInstitute of OceanologyChinese Academy of SciencesQingdao 266071China Laboratory for Marine Ecology and Environmental Science Pilot National Laboratory for Marine Science and Technology(Qingdao)Qingdao 266237China University of Chinese Academy of Sciences Beijing 100049China Center for Ocean Mega-Science Chinese Academy of SciencesQingdao 266071China

The moon jellyfi sh Aurelia spp.is a worldwide distributed scyphozoan species that seasonally blooms in coastal waters.Although the strobilation is directly responsible for the scale of jellyfi sh bloom,the underlying mechanisms remain largely unknown.We exposed Aurelia coerulea polyps to 18 bioactive substances to test their ability to induce strobilation at the natural typically non-strobilation temperature of 21°C.Results revealed that A.coerulea polyps responded in four types.Type I—no change for estradiol,folic acid,iodine,retinoic acid,serotonin hydrochloride,and vitamin A.We suggested that 5-aza-2-deoxycytidine and N-acetyl-L-glutamic acid could not induce strobilation,since the percent of strobilated polyps in these two substances treatments was 3.3%and 1%,respectively.Type II—polyp body elongation for 3,5-diiodo-Ltyrosine,indole-3-acetic acid,L-dopamine,and noradrenaline treatments.Type III—transverse constrictions for L-thyroxine,progesterone,and melatonin treatments.Finally,Type IV—complete strobilation for 5-methoxy-2-methylindole,acetylcholine chloride,and indomethacin treatments,where the pre-strobilation periods were 2,4,and 2 days,and the mean numbers of ephyrae released per strobila were 4.7,5.7,and 5.7,respectively.The results reveal that indole derivatives,which contained methoxy or methyl pharmacophore,were the common strobilation inducer in the genus Aurelia.Iodinated organic compounds,catecholamine,acetylcholine chloride,and retinoic acid are species-specifi c strobilation inducer.Therefore,A.coerulea strobilation is regulated by neuronal and endocrine processes.Our fi ndings provide clues in understanding the mechanism of strobilation and contribute to developing specifi c strobilation antagonists in controlling moon jellyfi sh blooms.

关键词： Aurelia coerulea jellyfi sh strobilation bioactive substances metamorphosis

Corrosion behavior of Mg-8li-3Zn-Al alloy in neutral 3.5%NaCl solution

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Journal of Magnesium and Alloys 2016年第1期4卷 22-26页

作者： lihui Yang Quantong Jiang Meng Zheng Baorong Hou Yantao LI Institute of Oceanology Chinese Academy of SciencesQingdao 266071China

The corrosion behavior of Mg-8li-3Zn-Al alloy was investigated in neutral 3.5%NaCl aqueous solution by morphology observation and electrochemical tests.The weight loss method was to measure the corrosion rate.The electrochemical results indicated that the corrosion resistance of Mg-8li-3Zn-Al alloy in 3.5%NaCl solution is poorer than that in distilled water.The Cl-anion leads to the initiation and development of the corrosion pits.And the corrosion products are mainly Mg(OH)_(2).

关键词： Mg-8li-3Zn-Al alloy Corrosion morphology Polarization curve