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Analysis of a Continuative Fog Event in Western Shandong Province
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作者 LI Jing GAO Liu-xi +1 位作者 CHEN Jin-min GAO Hui-jun 《Meteorological and Environmental Research》 2012年第7期19-22,34,共5页
[Objective] The aim was to study a continuative fog event in center and western Shandong Province from December 3 to 7 in 2011. [ Method] Based on regular meteorological data, a continuative heavy fog weather process ... [Objective] The aim was to study a continuative fog event in center and western Shandong Province from December 3 to 7 in 2011. [ Method] Based on regular meteorological data, a continuative heavy fog weather process during December 3 to 7 in 2011 was analyzed from the aspects of weather background, ground factors, T-Inp, and moisture and physical quantity field. [ Result] The heavy fog occurred under then at- mospheric circulation pattern controlled by the straight westerly air flow at 500 hPa middle latitudes, ridge of high pressure at middle and low levels, and weak pressure at the bottom of the surface high. The snowfall process for the formation of fog provided vapor conditions of fog, maintenance and development had benefited from lower layer of the warm and humid airflow. During the heavy fog, wind speed was between 1 and 3 m/s. The dew difference and visibility in the eady period had distinct daily changes, while the difference narrowed in the middle and later stage. Close to the ground was an obvious inversion layer, at the same time in the fog strong period temperature inversion layer were apparent between 700 and 800 hPa, these were helpful for fog formation and development. The stable atmospheric stratification, while low layer of weak convergence ascending motion, high level in the presence of weak divergence subsidence, these were also conducive to the maintenance and development of the fog. [ Conclusion] The study provided theoretical basis for the forecast of fog weather. 展开更多
关键词 continuative fog Western Shandong Province: Process analysis China
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Epigenetic memory of drug exposure history controls neural stem cell quiescence in the adult brain
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作者 Masakazu Iwamoto Taito Matsuda 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第4期711-712,共2页
Neural stem cells(NSCs)are the source of all neurons and glial cells(astrocytes and oligodendrocytes)in the central nervous system.The adult mammalian brain retains NSCs in the subgranular zone of the dentate gyrus in... Neural stem cells(NSCs)are the source of all neurons and glial cells(astrocytes and oligodendrocytes)in the central nervous system.The adult mammalian brain retains NSCs in the subgranular zone of the dentate gyrus in the hippocampus and ventricular subventricular zone lining the lateral ventricle(Olpe and Jessberger,2022).Adult NSCs in rodents are preserved throughout life and continuously produce new neurons that integrate into the pre-existing neuronal network. 展开更多
关键词 NEURAL INTEGRATE continuously
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Transforming agri-food systems for multiple wins in nutrition,inclusion and environment
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作者 Shenggen Fan Qiran Zhao Jingjing Wang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第2期355-358,共4页
The call for agri-food system transformation is urgent in many global development agendas(UN 2023).Food systems have contributed to economic prosperity and feeding the world,but they are also associated with numerous ... The call for agri-food system transformation is urgent in many global development agendas(UN 2023).Food systems have contributed to economic prosperity and feeding the world,but they are also associated with numerous challenges,including climate change,continued hunger,poor diets and malnutrition,and increasing disparities(Webb et al.2020;Fanzo et al.2021). 展开更多
关键词 continued NUTRITION URGENT
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A Discussion on the Flexible Regulation Capacity Requirements of China’s Power System
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作者 Qiang Zhao Yuqiong Zhang +3 位作者 Xiaoxin Zhou Ziwei Chen Huaguang Yan Honghua Yang 《Engineering》 SCIE EI CAS CSCD 2024年第2期12-16,共5页
A high proportion of variable renewable energy(VRE)is one of the most significant characteristics of China’s future power system under the"dual carbon"target.However,wind and solar power units are more unco... A high proportion of variable renewable energy(VRE)is one of the most significant characteristics of China’s future power system under the"dual carbon"target.However,wind and solar power units are more uncontrollable and less supportive for power system stability than traditional thermal power units,due to their susceptibility to the weather and the grid connection of power electronics.Therefore,as the capacity and generation of VRE grow rapidly and even dominate the power structure,the power system’s ability to deal with disturbances will continue to decrease. 展开更多
关键词 WEATHER CONTINUE SUSCEPTIBILITY
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Enhanced measurement precision with continuous interrogation during dynamical decoupling
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作者 张军 杜鹏 +3 位作者 敬雷 徐鹏 尤力 张文献 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第3期88-94,共7页
Dynamical decoupling(DD)is normally ineffective when applied to DC measurement.In its straightforward implementation,DD nulls out DC signal as well while suppressing noise.This work proposes a phase relay method that ... Dynamical decoupling(DD)is normally ineffective when applied to DC measurement.In its straightforward implementation,DD nulls out DC signal as well while suppressing noise.This work proposes a phase relay method that is capable of continuously interrogating the DC signal over many DD cycles.We illustrate its efficacy when applied to the measurement of a weak DC magnetic field with an atomic spinor Bose-Einstein condensate.Sensitivities approaching standard quantum limit or Heisenberg limit are potentially realizable for a coherent spin state or a squeezed spin state of 10000 atoms,respectively,while ambient laboratory level noise is suppressed by DD.Our work offers a practical approach to mitigate the limitations of DD to DC measurement and would find other applications for resorting coherence in quantum sensing and quantum information processing research. 展开更多
关键词 quantum sensing continuous interrogation quantum magnetometer dynamical decoupling Heisenberg limit
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Irregular initial solidification by mold thermal monitoring in the continuous casting of steels:A review
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作者 Qiuping Li Guanghua Wen +3 位作者 Fuhang Chen Ping Tang Zibing Hou Xinyun Mo 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第5期1003-1015,共13页
Occasional irregular initial solidification phenomena,including stickers,deep oscillation marks,depressions,and surface cracks of strand shells in continuous casting molds,are important limitations for developing the ... Occasional irregular initial solidification phenomena,including stickers,deep oscillation marks,depressions,and surface cracks of strand shells in continuous casting molds,are important limitations for developing the high-efficiency continuous casting of steels.The application of mold thermal monitoring(MTM) systems,which use thermocouples to detect and respond to temperature variations in molds,has become an effective method to address irregular initial solidification phenomena.Such systems are widely applied in numerous steel companies for sticker breakout prediction.However,monitoring the surface defects of strands remains immature.Hence,indepth research is necessary to utilize the potential advantages and comprehensive monitoring of MTM systems.This paper summarizes what is included in the irregular initial solidification phenomena and systematically reviews the current state of research on these phenomena by the MTM systems.Furthermore,the influences of mold slag behavior on monitoring these phenomena are analyzed.Finally,the remaining problems of the formation mechanisms and investigations of irregular initial solidification phenomena are discussed,and future research directions are proposed. 展开更多
关键词 irregular initial solidification mold thermal monitoring continuous casting mold slag THERMOCOUPLE
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八步连续流全合成维生素B_(1)工艺研究
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作者 Meifen Jiang Minjie Liu +2 位作者 Weijian Li Yingqi Xia Fen-Er Chen 《Engineering》 SCIE EI CAS CSCD 2024年第1期226-232,共7页
Vitamin B_(1) is widely applied in the healthcare and food industry as an antineuritic and antioxidant to maintain the normal functioning of nerve conduction,the heart,and the gastrointestinal tract.This study reports... Vitamin B_(1) is widely applied in the healthcare and food industry as an antineuritic and antioxidant to maintain the normal functioning of nerve conduction,the heart,and the gastrointestinal tract.This study reports on an integrated eight-step continuous-flow synthesis of vitamin B_(1) from commercially available 2-cyanoacetamide.The proposed continuous-flow process is based on advances in chemistry,engineering,and equipment design,and affords improved performance and safety compared with batch-mode manufacturing.Several challenges were precisely investigated and controlled,including mixing,unexpected clogging,solvent switches,an exothermic reaction,and the prevention of side reactions,using various micro-channel flow reactors,mixers,separators,and continuous filters.Vitamin B_(1) was produced with a separated yield of 47.7% and high purity,with a total residence time of about 3.5 h.This eight-step continuous-flow protocol enables technology involving up to six of the key principles of green chemistry.Hence,the application of flow technology is of paramount importance for improving security,reducing waste,and,in particular,improving the efficiency of batch operations that require several days for manufacturing. 展开更多
关键词 Vitamin B_(1) Continuous-flow synthesis MICRO-REACTOR Continuous manufacturing
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Instructions for Authors
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《International Journal of Ophthalmology(English edition)》 SCIE CAS 2024年第1期210-212,共3页
GENERAL INFORMATION International Journal of Ophthalmology—IJO,published continuously since 2008,a global ophthalmological scientific publication and a peer-reviewed,open access periodical published in print and onli... GENERAL INFORMATION International Journal of Ophthalmology—IJO,published continuously since 2008,a global ophthalmological scientific publication and a peer-reviewed,open access periodical published in print and online monthly(ISSN:2222-3959 print,ISSN:2227-4898 online).IJO is sponsored by the Chinese Medical Association Xi’an Branch,China and obtains guidance,and support from World Health Organization(WHO)and International Council of Ophthalmology(ICO). 展开更多
关键词 ISSN continuously GUIDANCE
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CAUCHY TYPE INTEGRALS AND A BOUNDARY VALUE PROBLEM IN A COMPLEX CLIFFORD ANALYSIS
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作者 曹南斌 李尊凤 +1 位作者 杨贺菊 乔玉英 《Acta Mathematica Scientia》 SCIE CSCD 2024年第1期369-385,共17页
Clifford analysis is an important branch of modern analysis;it has a very important theoretical significance and application value,and its conclusions can be applied to the Maxwell equation,Yang-Mill field theory,quan... Clifford analysis is an important branch of modern analysis;it has a very important theoretical significance and application value,and its conclusions can be applied to the Maxwell equation,Yang-Mill field theory,quantum mechanics and value problems.In this paper,we first give the definition of a quasi-Cauchy type integral in complex Clifford analysis,and get the Plemelj formula for it.Second,we discuss the H?lder continuity for the Cauchy-type integral operators with values in a complex Clifford algebra.Finally,we prove the existence of solutions for a class of linear boundary value problems and give the integral representation for the solution. 展开更多
关键词 Clifford analysis Cauchy type integral Plemelj formula Holder continuous boundary value problems
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Data Quality Control Method of a New Drifting Observation Technology Named Drifting Air-Sea Interface Buoy
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作者 LI Shuo WANG Bin +3 位作者 DENG Zeng’an WU Baoqin ZHU Xiande CHEN Zhaohui 《Journal of Ocean University of China》 CAS CSCD 2024年第1期11-22,共12页
An integral quality control(QC)procedure that integrates various QC methods and considers the design indexes and operational status of the instruments for the observations of drifting air-sea interface buoy was develo... An integral quality control(QC)procedure that integrates various QC methods and considers the design indexes and operational status of the instruments for the observations of drifting air-sea interface buoy was developed in the order of basic in-spection followed by targeted QC.The innovative method of combining a moving Hampel filter and local anomaly detection com-plies with statistical laws and physical processes,which guarantees the QC performance of meteorological variables.Two sets of observation data were used to verify the applicability and effectiveness of the QC procedure,and the effect was evaluated using the observations of the Kuroshio Extension Observatory buoy as the reference.The results showed that the outliers in the time series can be correctly identified and processed,and the quality of data improved significantly.The linear correlation between the quality-controlled observations and the reference increased,and the difference decreased.The correlation coefficient of wind speed before and after QC increased from 0.77 to 0.82,and the maximum absolute error decreased by approximately 2.8ms^(-1).In addition,air pressure and relative humidity were optimized by 10^(-3)–10^(-2) orders of magnitude.For the sea surface temperature,the weight of coefficients of the continuity test algorithm was optimized based on the sea area of data acquisition,which effectively expanded the applicability of the algorithm. 展开更多
关键词 drifting air-sea interface buoy quality control oceanic variables meteorological variables continuity test
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Suppressive effects of exercise-conditioned serum on cancer cells:A narrative review of the influence of exercise mode,volume,and intensity
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作者 Francesco Bettariga Dennis R.Taaffe +3 位作者 Daniel A.Galvao Chris Bishop Jin-Soo Kim Robert U.Newton 《Journal of Sport and Health Science》 SCIE CAS CSCD 2024年第4期484-498,F0003,共16页
Cancer is a major cause of morbidity and mortality worldwide,and the incidence is increasing,highlighting the need for effective strategies to treat this disease.Exercise has emerged as fundamental therapeutic medicin... Cancer is a major cause of morbidity and mortality worldwide,and the incidence is increasing,highlighting the need for effective strategies to treat this disease.Exercise has emerged as fundamental therapeutic medicine in the management of cancer,associated with a lower risk of recur-rence and increased survival.Several avenues of research demonstrate reduction in growth,proliferation,and increased apoptosis of cancer cells,including breast,prostate,colorectal,and lung cancer,when cultured by serum collected after exercise in vitro(i.e.,the cultivation of cancer cell lines in an experimental setting,which simplifies the biological system and provides mechanistic insight into cell responses).The underlying mechanisms of exercise-induced cancer suppressive effects may be attributed to the alteration in circulating factors,such as skeletal muscle-induced cytokines(i.e.,myokines)and hormones.However,exercise-induced tumor suppressive effects and detailed information about training interventions are not well investigated,constraining more precise application of exercise medicine within clinical oncology.To date,it remains unclear what role different training modes(i.e.,resistance and aerobic training)as well as volume and intensity have on exercise-condi-tioned serum and its effects on cancer cells.Nevertheless,the available evidence is that a single bout of aerobic training at moderate to vigorous intensity has cancer suppressive effects,while for chronic training interventions,exercise volume appears to be an influential candidate driving cancer inhibitory effects regardless of training mode.Insights for future research investigating training modes,volume and intensity are provided to further our understanding of the effects of exercise-conditioned serum on cancer cells. 展开更多
关键词 Cancer cells High intensity interval training Moderate intensity continuous training Resistance training MYOKINES
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Microarrow sensor array with enhanced skin adhesion for transdermal continuous monitoring of glucose and reactive oxygen species
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作者 Xinshuo Huang Baoming Liang +9 位作者 Shantao Zheng Feifei Wu Mengyi He Shuang Huang Jingbo Yang Qiangqiang Ouyang Fanmao Liu Jing Liu Hui-jiuan Chen Xi Xie 《Bio-Design and Manufacturing》 SCIE EI CAS CSCD 2024年第1期14-30,共17页
Conventional blood sampling for glucose detection is prone to cause pain and fails to continuously record glucose fluctuations in vivo.Continuous glucose monitoring based on implantable electrodes could induce pain an... Conventional blood sampling for glucose detection is prone to cause pain and fails to continuously record glucose fluctuations in vivo.Continuous glucose monitoring based on implantable electrodes could induce pain and potential tissue inflammation,and the presence of reactive oxygen species(ROS)due to inflammationmay affect glucose detection.Microneedle technology is less invasive,yet microneedle adhesion with skin tissue is limited.In this work,we developed a microarrow sensor array(MASA),which provided enhanced skin surface adhesion and enabled simultaneous detection of glucose and H_(2)O_(2)(representative of ROS)in interstitial fluid in vivo.The microarrows fabricated via laser micromachining were modified with functional coating and integrated into a patch of a three-dimensional(3D)microneedle array.Due to the arrow tip mechanically interlocking with the tissue,the microarrow array could better adhere to the skin surface after penetration into skin.The MASA was demonstrated to provide continuous in vivo monitoring of glucose and H_(2)O_(2) concentrations,with the detection of H_(2)O_(2) providing a valuable reference for assessing the inflammation state.Finally,the MASA was integrated into a monitoring system using custom circuitry.This work provides a promising tool for the stable and reliable monitoring of blood glucose in diabetic patients. 展开更多
关键词 Microarrow sensor array Glucose sensing Reactive oxygen species sensing Integrated system Continuous monitoring
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美国《保健物理》(Health Physics)杂志英文摘要(2023年125卷第4期)(英文)
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《辐射防护》 CAS CSCD 北大核心 2024年第1期93-97,共5页
Fetal and Maternal Atomic Bomb Survivor Dosimetry Using the J45 Pregnant Female Phantom Series:Considerations of the Kneeling and Lying Posture with Comparisons to the DS02 System Sean J.Domal1,Camilo M.Correa-Alfonso... Fetal and Maternal Atomic Bomb Survivor Dosimetry Using the J45 Pregnant Female Phantom Series:Considerations of the Kneeling and Lying Posture with Comparisons to the DS02 System Sean J.Domal1,Camilo M.Correa-Alfonso1,Colin J.Paulbeck2,Keith T.Griffin3,4,Tatsuhiko Sato5,Sachiyo Funamoto6,Harry M.Cullings6,Stephen D.Egbert7,Akira Endo8,Nolan E.Hertel4,Choonsik Lee3,Wesley E.Bolch9(1.Medical Physics Program,College of Medicine,University of Florida,Gainesville,FL;2.Department of Radiology,Johns Hopkins University,Baltimore,MD;3.National Cancer Institute,National Institutes of Health,Rockville,MD;4.George W.Woodruff School of Mechanical Eng.,Georgia Institute of Technology,Atlanta,GA;5.Nuclear Science and Engineering Center,Japan Atomic Energy Agency,Tokaimura,Japan;6.Department of Statistics,Radiation Effects Research Foundation,Hiroshima,Japan;7.Consultant,San Diego,CA;8.Nuclear Science Research Institute,Japan Atomic Energy Agency,Tokaimura,Japan;9.J.Crayton Pruitt Family Department of Biomedical Eng.,University of Florida,Gainesville,FL USA)Abstract:Organ dosimetry data of the atomic bomb survivors and the resulting cancer risk models derived from these data are currently assessed within the DS02 dosimetry system developed through the Joint US-Japan Dosimetry Working Group.In DS02,the anatomical survivor models are limited to three hermaphroditic stylized phantoms—an adult(55 kg),a child(19.8 kg),and an infant(9.7 kg)—that were originally designed for the preceding DS86 dosimetry system.As such,organ doses needed for assessment of in-utero cancer risks to the fetus have continued to rely upon the use of the uterine wall in the adult non-pregnant stylized phantom as the dose surrogate for all fetal organs regardless of gestational age. 展开更多
关键词 doses 英文摘要 continued
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Regulating the non-effective carriers transport for high-performance lithium metal batteries
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作者 Simeng Wang Youchun Yu +2 位作者 Shaotong Fu Hongtao Li Jiajia Huang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第5期132-141,共10页
The absence of control over carriers transport during electrochemical cycling,accompanied by the deterioration of the solid electrolyte interphase(SEI)and the growth of lithium dendrites,has hindered the development o... The absence of control over carriers transport during electrochemical cycling,accompanied by the deterioration of the solid electrolyte interphase(SEI)and the growth of lithium dendrites,has hindered the development of lithium metal batteries.Herein,a separator complexion consisting of polyacrylonitrile(PAN)nanofiber and MIL-101(Cr)particles prepared by electrospinning is proposed to bind the anions from the electrolyte utilizing abundant effective open metal sites in the MIL-101(Cr)particles to modulate the transport of non-effective carriers.The binding effect of the PANM separator promotes uniform lithium metal deposition and enhances the stability of the SEI layer and long cycling stability of ultra-high nickel layered oxide cathodes.Taking PANM as the Li||NCM96 separator enables high-voltage cycling stability,maintaining 72%capacity retention after 800 cycles at a charging and discharging rate of 0.2 C at a cut-off voltage of 4.5 V and 0°C.Meanwhile,the excellent high-rate performance delivers a specific capacity of 156.3 mA h g^(-1) at 10 C.In addition,outstanding cycling performance is realized from−20 to 60°C.The separator engineering facilitates the electrochemical performance of lithium metal batteries and enlightens a facile and promising strategy to develop fast charge/discharge over a wide range of temperatures. 展开更多
关键词 Functional separators Metal-organic frameworks 3D continuous ion transport networks ELECTROSPINNING Lithium metal batteries
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NADARAYA-WATSON ESTIMATORS FOR REFLECTED STOCHASTIC PROCESSES
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作者 韩月才 张丁文 《Acta Mathematica Scientia》 SCIE CSCD 2024年第1期143-160,共18页
We study the Nadaraya-Watson estimators for the drift function of two-sided reflected stochastic differential equations.The estimates,based on either the continuously observed process or the discretely observed proces... We study the Nadaraya-Watson estimators for the drift function of two-sided reflected stochastic differential equations.The estimates,based on either the continuously observed process or the discretely observed process,are considered.Under certain conditions,we prove the strong consistency and the asymptotic normality of the two estimators.Our method is also suitable for one-sided reflected stochastic differential equations.Simulation results demonstrate that the performance of our estimator is superior to that of the estimator proposed by Cholaquidis et al.(Stat Sin,2021,31:29-51).Several real data sets of the currency exchange rate are used to illustrate our proposed methodology. 展开更多
关键词 reflected stochastic differential equation discretely observed process continuously observed process Nadaraya-Watson estimator asymptotic behavior
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Auto-parametric resonance of a continuous-beam-bridge model under two-point periodic excitation:an experimental investigation and stability analysis
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作者 Li Yuchun Shen Chao +1 位作者 Liu Wei Li Dong 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2024年第2期445-454,共10页
The auto-parametric resonance of a continuous-beam bridge model subjected to a two-point periodic excitation is experimentally and numerically investigated in this study.An auto-parametric resonance experiment of the ... The auto-parametric resonance of a continuous-beam bridge model subjected to a two-point periodic excitation is experimentally and numerically investigated in this study.An auto-parametric resonance experiment of the test model is conducted to observe and measure the auto-parametric resonance of a continuous beam under a two-point excitation on columns.The parametric vibration equation is established for the test model using the finite-element method.The auto-parametric resonance stability of the structure is analyzed by using Newmark's method and the energy-growth exponent method.The effects of the phase difference of the two-point excitation on the stability boundaries of auto-parametric resonance are studied for the test model.Compared with the experiment,the numerical instability predictions of auto-parametric resonance are consistent with the test phenomena,and the numerical stability boundaries of auto-parametric resonance agree with the experimental ones.For a continuous beam bridge,when the ratio of multipoint excitation frequency(applied to the columns)to natural frequency of the continuous girder is approximately equal to 2,the continuous beam may undergo a strong auto-parametric resonance.Combined with the present experiment and analysis,a hypothesis of Volgograd Bridge's serpentine vibration is discussed. 展开更多
关键词 auto-parametric resonance continuous beam bridge model two-point excitation experimental investigation stability analysis vibration of Volgograd Bridge
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Optimal confrontation position selecting games model and its application to one-on-one air combat
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作者 Zekun Duan Genjiu Xu +2 位作者 Xin Liu Jiayuan Ma Liying Wang 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第1期417-428,共12页
In the air combat process,confrontation position is the critical factor to determine the confrontation situation,attack effect and escape probability of UAVs.Therefore,selecting the optimal confrontation position beco... In the air combat process,confrontation position is the critical factor to determine the confrontation situation,attack effect and escape probability of UAVs.Therefore,selecting the optimal confrontation position becomes the primary goal of maneuver decision-making.By taking the position as the UAV’s maneuver strategy,this paper constructs the optimal confrontation position selecting games(OCPSGs)model.In the OCPSGs model,the payoff function of each UAV is defined by the difference between the comprehensive advantages of both sides,and the strategy space of each UAV at every step is defined by its accessible space determined by the maneuverability.Then we design the limit approximation of mixed strategy Nash equilibrium(LAMSNQ)algorithm,which provides a method to determine the optimal probability distribution of positions in the strategy space.In the simulation phase,we assume the motions on three directions are independent and the strategy space is a cuboid to simplify the model.Several simulations are performed to verify the feasibility,effectiveness and stability of the algorithm. 展开更多
关键词 Unmanned aerial vehicles(UAVs) Air combat Continuous strategy space Mixed strategy Nash equilibrium
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THE ABSENCE OF SINGULAR CONTINUOUS SPECTRUM FOR PERTURBED JACOBI OPERATORS
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作者 傅钲淇 黎雄 《Acta Mathematica Scientia》 SCIE CSCD 2024年第2期515-531,共17页
This paper is mainly about the spectral properties of a class of Jacobi operators(H_(c,b)u)(n)=c_(n)u(n+1)+c_(n-1)u(n-1)+b_(n)u(n),.where∣c_(n)−1∣=O(n^(−α))and b_(n)=O(n^(−1)).We will show that,forα≥1,the singula... This paper is mainly about the spectral properties of a class of Jacobi operators(H_(c,b)u)(n)=c_(n)u(n+1)+c_(n-1)u(n-1)+b_(n)u(n),.where∣c_(n)−1∣=O(n^(−α))and b_(n)=O(n^(−1)).We will show that,forα≥1,the singular continuous spectrum of the operator is empty. 展开更多
关键词 Jacobi operator singular continuous spectrum Prüfer variables
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Microstructure and properties of LZQT600-3 HCCDIBs for plunger pump cylinder
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作者 Chun-jie Xu Yuan-ying Jin +8 位作者 Dong Ma Zhen Zhao Jia-wei Qi Shang Sui Xiang-quan Wu Can Guo Zhong-ming Zhang Yong-hui Liu Dan Shechtman 《China Foundry》 SCIE EI CAS CSCD 2024年第2期197-204,共8页
It is important to improve the comprehensive performance of the ductile iron bars(DIBs)for the cylinder block of the extra high pressure hydraulic plunger pump and accelerate the industrial application.In this work,th... It is important to improve the comprehensive performance of the ductile iron bars(DIBs)for the cylinder block of the extra high pressure hydraulic plunger pump and accelerate the industrial application.In this work,the LZQT600-3 DIBs with the diameter of 145 mm were prepared by the horizontal continuous casting(HCC)process,that is,LZQT600-3 HCCDIBs.The microstructure and room temperature tensile properties of different sections[left-edge(surface layer),left-1/2R(left half of the radius),and the center of the HCCDIBs]were studied.The results show that the spheroidization of LZQT600-3 HCCDIBs matrix from the left-edge,left-1/2R to the center is at nodulizing grade II and above.As the cooling rate gradually decreases from surface to the center of the HCCIBs,the number of spheroidized graphite is gradually reduced,the size is gradually increased,the shape factor is decreased,and the pearlite content and lamellate spacing are increased.Along the horizontal direction of the section,the hardness of the material is distributed symmetrically around the center of the HCCDIBs.In the vertical direction,the hardness distribution in the center of the HCCDIBs is asymmetrical due to the gravity during the solidification process.Therefore,the microstructure in the lower part of the section solidifies relatively quickly.The left-edge has the best tensile mechanical properties,and the ultimate tensile strength,yield tensile strength and elongation are 597.3 MPa,418.5 MPa and 9.6%,respectively.The tensile fracture belongs to the ductile-brittle hybrid fracture.The comprehensive performances of LZQT600-3 HCCDIBs meet the actual application requirements of ultra-high pressure hydraulic plunger pump cylinder. 展开更多
关键词 horizontal continuous casting(HCC) nodular cast iron ductile iron bars microstructure mechanical properties
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Effect of droplet characteristics on liquid-phase distribution in spray zone of internal mixing air-mist nozzle
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作者 Wei-li Wu Chang-gui Cheng +2 位作者 Yang Li Shi-fa Wei De-li Chen 《China Foundry》 SCIE EI CAS CSCD 2024年第2期185-196,共12页
In continuous casting production,droplet characteristics are important parameters for evaluating the nozzle atomization quality,and have a significant impact on the secondary cooling effect and the slab quality.In ord... In continuous casting production,droplet characteristics are important parameters for evaluating the nozzle atomization quality,and have a significant impact on the secondary cooling effect and the slab quality.In order to study the behavior of atomized droplets after reaching the slab surface and to optimize the spray cooling effect,the influence of droplet diameter and droplet velocity on the migration behavior of droplets in the secondary cooling zone was analyzed by FLUENT software.Results show that the droplets in the spray zone and on the slab surface are mainly concentrated in the center,thus,the liquid volume fraction in the center is higher than that of either side.As the droplet diameter increases,the region of high liquid volume fraction on the slab surface becomes wider,and the liquid phase distribution in the slab width direction becomes uneven.Although increasing the droplet velocity at the nozzle exit has little effect on droplet diffusion in the spray zone,the distribution becomes more uneven due to more liquid reaches the slab surface per unit time.A prediction formula of the maximum water flow rate on the slab surface for specific droplet characteristics was proposed based on dimensionless analysis and validated by simulated data.A nozzle spacing of 210 mm was recommended under the working conditions in this study,which ensures effective coverage of the spray water over the slab surface and enhances the distribution uniformity of water flow rate in the transverse direction. 展开更多
关键词 continuous casting secondary cooling zone internal mixing air-mist nozzle droplet characteristics liquid phase distribution water flow rate
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