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Advances in Climate Change Research 2024年第4期15卷 573-583页

作者： Jun liu Xiao-Fan WANG dong-You WU xin WANG Key Laboratory for Semi-Arid Climate Change of the Ministry of Education College of Atmospheric SciencesLanzhou UniversityLanzhou 730000China

Arctic warming played a dominant role in recent occurrences of extreme events over the Northern Hemisphere,but climate models cannot accurately simulate the *** a significant positive correlation(0.33-0.95)between extreme precipitation and Arctic amplification(AA)is found using observations and CMIP5/6 multi-model ***,CMIP6 models are superior to CMIP5 models in simulating the temporal evolution of extreme precipitation and *** to 14 optimal CMIP6 models,the maximum latitude of planetary waves and the strength of Northern Hemisphere annular mode(NAM)will increase with increasing AA,contributing to increased extreme precipitation over the Northern *** the Shared Socioeconomic Pathway SSP5-8.5,AA is expected to increase by 0.85℃ per decade while the maximum latitude of planetary waves will increase by 2.82°per ***,the amplitude of the NAM will increase by 0.21 hPa per decade,contributing to a rise in extreme precipitation of 1.17% per decade for R95pTOT and 0.86% per decade for R99pTOT by 2100.

关键词： Arctic amplification Extreme precipitation CMIP5 CMIP6 Model evaluation Planetary waves Northern hemisphere annular mode

Distributed collaborative complete coverage path planning based on hybrid strategy

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Journal of Systems Engineering and Electronics 2024年第2期35卷 463-472页

作者： ZHANG Jia DU xin dong Qichen xin Bin School of Automation Beijing Institute of TechnologyBeijing 100081China National Key Laboratory of Autonomous Intelligent Unmanned Systems Beijing Institute of TechnologyBeijing 100081China

Collaborative coverage path planning(CCPP) refers to obtaining the shortest paths passing over all places except obstacles in a certain area or space. A multi-unmanned aerial vehicle(UAV) collaborative CCPP algorithm is proposed for the urban rescue search or military search in outdoor *** to flexible control of small UAVs, it can be considered that all UAVs fly at the same altitude, that is, they perform search tasks on a two-dimensional plane. Based on the agents’ motion characteristics and environmental information, a mathematical model of CCPP problem is established. The minimum time for UAVs to complete the CCPP is the objective function, and complete coverage constraint, no-fly constraint, collision avoidance constraint, and communication constraint are considered. Four motion strategies and two communication strategies are designed. Then a distributed CCPP algorithm is designed based on hybrid strategies. Simulation results compared with patternbased genetic algorithm(PBGA) and random search method show that the proposed method has stronger real-time performance and better scalability and can complete the complete CCPP task more efficiently and stably.

关键词： multi-agent cooperation unmanned aerial vehicles(UAV) distributed algorithm complete coverage path planning(CCPP)

Poles Extraction Based LiDAR Localization for Autonomous Robot Systems

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Journal of Systems Science & Complexity 2024年第4期37卷 1413-1424页

作者： HONG xin dong Yi College of Electronic and Information Engineering Tongji UniversityShanghai 201800China

With the development of intelligent technology,the problem of Li DAR-based localization has played an increasingly important role in the localization of robots in unmanned *** the dense point clouds from the environment requires a large amount of memory,specific and stable structural features,such as pole-like objects in the environment,can serve as the ideal landmarks for localization in unmanned systems,which can effectively reduce the memory usage and mitigate the effects of dynamic environment *** this paper,the authors propose a pole-like objects extraction approach and then,it is applied into the localization system of mobile *** the same experimental conditions,the proposed method can extract more pole-like objects and achieve better long-term localization accuracy than some existing methods in different urban environmental datasets.

关键词： Pole-like landmark extraction robot localization

A reweighted damped singular spectrum analysis method for robust seismic noise suppression

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Petroleum Science 2024年第3期21卷 1671-1682页

作者： Wei-Lin Huang Yan-xin Zhou Yang Zhou Wei-Jie liu Ji-dong Li State Key Laboratory of Petroleum Resources and Engineering China University of Petroleum(Beijing)Beijing2249China SINOPEC Petroleum Exploration and Production Research Institute Beijing102206China SINOPEC Geophysical Research Institute Nanjing211103jiangsuChina

(Multichannel)Singular spectrum analysis is considered as one of the most effective methods for seismic incoherent noise *** utilizes the low-rank feature of seismic signal and regards the noise suppression as a low-rank reconstruction ***,in some cases the seismic geophones receive some erratic disturbances and the amplitudes are dramatically larger than other *** presence of this kind of noise,called erratic noise,makes singular spectrum analysis(SSA)reconstruction unstable and has undesirable effects on the final *** robustify the low-rank reconstruction of seismic data by a reweighted damped SSA(RD-SSA)*** incorporates the damped SSA,an improved version of SSA,into a reweighted *** damping operator is used to weaken the artificial disturbance introduced by the low-rank projection of both erratic and random *** central idea of the RD-SSA method is to iteratively approximate the observed data with the quadratic norm for the first iteration and the Tukeys bisquare norm for the rest *** RD-SSA method can suppress seismic incoherent noise and keep the reconstruction process robust to the erratic *** feasibility of RD-SSA is validated via both synthetic and field data examples.

关键词： Singular spectrum analysis Damping operator Seismic erratic noise Seismic signal processing Robust low-rank reconstruction

Simulation study on cuttings transport of the backreaming operation for long horizontal section wells

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Petroleum Science 2024年第2期21卷 1149-1170页

作者： Yu-Fei Chen Hui Zhang Wen-xin Wu Jun Li Yong Ouyang Zong-Yu Lu De-xin Ma Yong-Chuan Wu Jun-Bo liu Ke-Rou liu Zhuo-xin dong China University of Petroleum(Beijing) Beijing102249China Beijing Normal University at Zhuhai Experimental and Practical Education Innovation CenterZhuhai519087GuangdongChina Oil&Gas Technology Research Institute of PetroChina Changqing Oilfield Company Xi'an710016ShaanxiChina PetroChina xinjiang Oilfield Company Karamay834002XinjiangChina China Oilfield Services Ltd. Tianjin300459China

The backreaming operation plays a significant role in safe drilling for horizontal wellbores, while it may cause severe stuck pipe accidents. To lower the risk of the stuck pipe in backreaming operations, the mechanism of cuttings transport needs to be carefully investigated. In this research, a transient cuttings transport with multiple flow patterns model is developed to predict the evolution of cuttings transported in the annulus while backreaming. The established model can provide predictions of the distribution of cuttings bed along the wellbore considering the bulldozer effect caused by large-size drilling tools(LSDTs). The sensitivity analyses of the size of LSDTs, and backreaming operating parameters are conducted in Section 4. And a new theory is proposed to explain the mechanism of cuttings transport in the backreaming operation, in which both the bit and LSDTs have the “cleaning effect” and “plugging effect”.The results demonstrate that the cuttings bed in annuli is in a state of dynamic equilibrium, but the overall trend and the distribution pattern are obvious. First, larger diameters and longer drilling tools could lead to a higher risk of the stuck pipe. Second, we find that it is not the case that the higher flow rate is always better for hole cleaning, so three flow-rate intervals are discussed separately under the given conditions. When the “dangerous flow rate”(35 L/s in Case 4),the higher the flow rate, the better the cleaning effect of cuttings beds. Third, an interval of tripping velocity called “dangerous velocity” is proposed, in which the cuttings bed accumulation near the LSDTs is more serious than

关键词： Backreaming Stuck pipe Hole cleaning Transient solid transport Multiple flow patterns

Dissolution kinetics and reaction mechanism of Al_(2)O_(3) in molten CaF_(2)-CaO-Al_(2)O_(3) slag

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Journal of Iron and Steel Research International 2024年第4期31卷 861-869页

作者： Yao-xin Du Yan-wu dong Zhou-hua Jiang Ganna Stovpchenko Yu-shuo Li Jun Huang xin-wei Wang Yu-xiao liu School of Metallurgy Northeastern UniversityShenyang 110819LiaoningChina Key Laboratory of Ecological Metallurgy of Multimetallic Mineral Northeastern UniversityShenyang 110819LiaoningChina State Key Laboratory of Rolling and Automation Northeastern UniversityShenyang 110819LiaoningChina E.O.Paton Electric Welding Institute of the National Academy of Science of Ukraine Kiev 03115Ukraine

The dissolution behavior of Al_(2)O_(3) in molten CaF_(2)-CaO-Al_(2)O_(3) slag,a basic slag system of electroslag remelting process,was investigated by rotating cylinder method using corundum rods to simulate Al_(2)O_(3) inclusions in *** experimental results show that the dissolution rate of Al_(2)O_(3);rods in CaF_(2)-CaO-Al_(2)O_(3) slag increases with the increase in rotating speed and temperature,and the rate-controlling step is the mass transfer in the *** dissolution rate of Al_(2)O,in CaF_(2)-CaO-Al_(2)O_(3) slag increases with the increase in the ratio of CaO to Al_(2)O_(3),which is due to the increase in dissolution driving force and the decrease in slag *** apparent activation energy of the mass transfer of AlOs in slag C is calculated to be 222.86 kJ mol^(-1).During the dissolution of Al_(2)0,inclusions in the slag,it reacts with F in liquid slag at first,then reacts with CaO to form the intermediate compounds of xCaO-yAl_(2)O_(3) system,and finally dissolves in molten *** dissolution rate of Al_(2)O_(3) inclusions in CaF_(2)-CaO-Al_(2)O_(3) slag for electroslag remelting is positively correlated with the ratio of the dissolution driving force and slag viscosity,and the correlation coeficient is 2.487×10^(-11).

关键词： Inclusion Electroslag remelting Mass transfer:Dissolution rate-Dissolution driving force

Modeling urban scale human mobility through big data analysis and machinelearning

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Building Simulation 2024年第1期17卷 3-21页

作者： Yapan liu Bing dong Department of Mechanical&Aerospace Engineering Syracuse University263 Link HallSyracuseNY 13244USA

In the United States,the buildings sector consumes about 76%of electricity use and 40% of all primary energy use and associated greenhouse gas *** behavior has drawn increasing research interests due to its impacts on the building energy ***,occupant behavior study at urban scale remains a challenge,and very limited studies have been *** an effort to couple big data analysis with human mobility modeling,this study has explored urban scale human mobility utilizing three months Global Positioning System(GPS)data of 93,o00 users at Phoenix Metropolitan *** research extracted stay points from raw data,and identified users'home,work,and other locations by Density-Based Spatial Clustering ***,daily mobility patterns were constructed using different types of *** propose a novel approach to predict urban scale daily human mobility patterns with 12-hour prediction horizon,using Long Short-Term Memory(LSTM)neural network *** shows the developed models achieved around 85%average accuracy and about 86%mean *** developed models can be further applied to analyze urban scale occupant behavior,building energy demand and flexibility,and contributed to urban planning.

关键词： urban human mobility big data analysis urban scale occupant behavior recurrent neural networks

In-situ warming does not change soil priming effect induced by glucose addition in a temperate forest

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Pedosphere 2024年第4期34卷 759-769页

作者： Xiaohan dong Yunting FANG dongwei liu xin GUAN Kai HUANG Yuqi liu Qingkui WANG Silong WANG Weidong ZHANG Huitong Experimental Station of Forest Ecology CAS Key Laboratory of Forest Ecology and ManagementInstitute of Applied EcologyShenyang 110016China University of Chinese Academy of Sciences Beijing 101408China Hunan Key Laboratory for Structure and Ecosystem Service of Subtropical Forest Huitong National Research Station of Forest EcosystemHuitong 418307China Qingyuan Forest Chinese Ecosystem Research Network(CERN) National Observation and Research StationShenyang 110016China Key Laboratory of Forest Ecology and Management Institute of Applied EcologyChinese Academy of SciencesShenyang 110016(China)f Key Laboratory of Stable Isotope Techniques and ApplicationsShenyang 110016China Key Laboratory of Terrestrial Ecosystem Carbon Neutrality Shenyang 110016China

Priming effect(PE)on soil organic carbon(SOC)decomposition caused by the addition of organic carbon(C)is an important ecological process in regulating soil C ***,most priming studies are confined to laboratory trials,while the assessment of soil PE under field conditions with variable weather conditions is *** study assessed the direct effects of glucose addition and in-situ warming on the extent of PE under field conditions in a temperate *** evaluated soil PE using 13C-glucose labelling,a simple and novel technique,based on the Keeling plot *** addition significantly enhanced native SOC decomposition and induced strong ***,the effect of in-situ warming on the extent of PE was not *** study confirms the importance of PE in regulating SOC turnover under field conditions.

关键词： lue lblling tchnquegbal wamingrmingt hppidfaty ai solganmattermineralisatn oezme respiration

Mechanical characteristics and reservoir stimulation mechanisms of the Gulong shale oil reservoirs, the northern Songliao Basin

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Petroleum Science 2024年第3期21卷 2023-2036页

作者： Si-Wei Meng Jia-Ping Tao Tian-Jiao Li dong-Xu Li Su-Ling Wang liu Yang xin liu Li-Hao Liang He liu PetroChina Research Institute of Petroleum Exploration Development Beijing100083China National Key Laboratory of Continental Shale Oil Daqing 163002HeilongjiangChina Dalian University of Technology Dalian116024LiaoningChina PetroChina Daqing Oilfield Co.Ltd. Daqing163002HeilongjiangChina Northeast Petroleum University Daqing163002HeilongjiangChina China University of Mining and Technology(Beijing) Beijing100083China

Shale oil of the Qingshankou Formation of the Gulong Sag,the northern Songliao Basin,represents the first attempt at large-scale development of pure-shale-type shale oil in *** integrating the multiscale refined reservoir characterization with macro-micro-scale mechanical testing,it is clarified that the Gulong shale is characterized by high clay mineral content,high rock plasticity,highly-developed bedding,and prominent mechanical anisotropy.A three-dimensional(3D)fracture propagation model of hydraulic fracturing was built for the Gulong shale,which fully captures the hydraulic fracture distribution pattern affected by the high bedding density,in-situ stress,and fracturing treatment *** research showed that due to influences of bedding,hydraulic fracturing in the Gulong shale forms a complex fracture morphology featuring the main fracture with multiple perpendicular branches that have different lengths(like the outdoor directional TV antenna);however,the vertical propagation of fractures is inhibited,and the fracture height is commonly less than 10 *** limited stimulated reservoir volume(SRV)is the main problem facing the fracturing stimulation of the Gulong shale *** density has vital effects on fracture morphology,so case-specific fracturing designs shall be developed for shale intervals with different bedding development *** reservoirs with welldeveloped bedding,it is suggested to properly increase the perforation cluster spacing and raise the volume and proportions of viscous fluids of the pad,so as to effectively promote vertical fracture propagation and improve reservoir stimulation *** study integrates multi-scale fine reservoir characterization and macro-micro-scale mechanical testing,as well as the construction and numerical simulation of hydraulic fracturing models for high-density layered shale reservoirs,providing a new approach and methodological framework for the fracturing research of high-density layer

关键词： Shale oil Hydraulic fracturing High bedding density Fracture propagation model

D-band center coordination modulated enzyme-like activity in Fe-Cu dual-metal single-atom nanozymes

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Nano Research 2024年第7期17卷 5872-5883页

作者： Ling liu Shaofang Zhang Guo Li Yadong Zhe Jiamin liu xinxu Zhang Jiahao Wei xin Sun Yonghui Li Xiao-dong Zhang Tianjin Key Laboratory of Brain Science and Neural Engineering Academy of Medical Engineering and Translational MedicineTianjin UniversityTianjin 300072China Department of Physics and Tianjin Key Laboratory of Low Dimensional Materials Physics and Preparing Technology School of SciencesTianjin UniversityTianjin 300350China

After explorations in a diversity of single-atom nanozymes(SAzymes),developing dual-centered SAzymes becomes a promising approach for superior catalytic *** confusing mechanisms including atomic coordination,spatial configuration,and metal–metal atom interaction hinder the development and design of ***,a dual-centered Fe-Cu-N_(x)SAzyme exhibits excellent peroxidase(POD)-and catalase(CAT)-like activities with d-band center(ε_(d))coordination of Fe and Cu in multiple reaction stages,which plays a critical role in the adsorption of H_(2)O_(2)molecule and H_(2)O and O_(2)***,the dband center coordination,which can be represented byε_(d)(Fe)–ε_(d)(Cu)shifts,leads to the competition between one-side and bilateral adsorption,which determines the favorable reaction path with lower energy *** on experimental statistics,simulated formation energies,and reaction barriers,3 configurations,Fe-Cu-N6-I,Fe-Cu-N_(8)-II,and Fe-Cu-N_(8)-III,are modeled and ***,configuration-dependent catalytic selectivity and the competition between one-side and bilateral adsorption can be unveiled by d-band center coordination paradigm *** simulations suggest that the unsymmetrical charge distribution over the three Fe-Cu configurations could tune the adsorption strength compared with the counterparts FeN_(4)and CuN_(4).The present work provides a potential route for optimizing enzyme-like catalysis by designing the dual-or even triple-metal SAzymes,which demonstrates the large space to modulate the metal atomic configuration and interaction.

关键词： single-atom catalysis Fe-Cu dual-metal d-band center coordination enzyme mimicking competitive adsorption mechanisms