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Mesospheric tide comparisons at low latitudes observed by two collocated meteor radars

Earth and Planetary Physics 2025年第1期9卷 54-68页

作者： Jian Li Wen Yi XiangHui Xue jie zeng HaiLun Ye JianYuan Wang JinSong Chen Na Li TingDi Chen Chinese Academy of Sciences(CAS)Key Laboratory of Geospace Environment Department of Geophysics and Planetary SciencesUniversity of Science and Technology of ChinaHefei 230026China CAS Center for Excellence in Comparative Planetology Anhui Mengcheng Geophysics National Observation and Research StationUniversity of Science and Technology of ChinaHefei 230026China Hefei National Laboratory University of Science and Technology of ChinaHefei 230026China Collaborative Innovation Center of Astronautical Science and Technology Harbin 150001China National Key Laboratory of Electromagnetic Environment China Research Institute of Radiowave PropagationQingdao 266107China Yunnan Kunming Electromagnetic Environment National Observation and Research Station Qujing Kunming 655000China

Accurate knowledge of mesospheric winds and waves is essential for studying the dynamics and climate in the mesosphere and lower thermosphere(MLT)*** this study,we conduct a comparative analysis of the mesosphere tidal results obtained from two adjacent meteor radars at low latitudes in Kunming,China,from November 2013 to December *** two radars operate at different frequencies of 37.5 MHz and 53.1 MHz,***,overall good agreement is observed between the two radars in terms of horizontal winds and tide *** results show that the dominant tidal waves of the zonal and meridional winds are diurnal and semidiurnal ***,we conduct an exhaustive statistical analysis to compare the tidal amplitudes and vertical wavelengths recorded by the dual radar systems,which reveals a high degree of alignment in tidal *** investigation includes variances and covariances of tidal amplitudes,which demonstrate remarkable consistency across measurements from both *** finding highlights clear uniformity in the mesospheric tidal patterns observed at low latitudes by the two neighboring meteor *** of the comparative analysis specifically underscore the significant correlation in vertical wavelength measurements,validating the robustness of radar observations for tidal research.

关键词： mesosphere and lower thermosphere region meteor radar mesospheric winds tides

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The midas touch on copper into palladium

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Science China Chemistry 2020年第12期63卷 1740-1741页

作者： jie zeng Hefei National Laboratory for Physical Sciences at the Microscale Department of Chemical PhysicsUniversity of Science and Technology of ChinaHefei 230026China

The catalytic semi-hydrogenation of alkynes(C≡C) to alkenes(C=C) has long been a crucial and challenging step in industry as it restrains the tendency of over-hydrogenation towards substrates [1]. Up to now, Pd-based catalysts show ultrahigh activity and selectivity towards the semihydrogenation of alkynes and are commonly used in industry, while metals such as Cu, Ag and Au exhibit relatively low activity due to their poor hydrogen activation ability.

关键词： hydrogenation palladium semi

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Twin-roll strip casting of advanced metallic materials

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Science China(Technological Sciences) 2022年第3期65卷 493-518页

作者： ZHU ChenYang zeng jie WANG WanLin School of Metallurgy and Environment Central South UniversityChangsha 410083China National Center for International Research of Clean Metallurgy Central South UniversityChangsha 410083China Department of Materials Science and Engineering Faculty of EngineeringNational University of SingaporeSingapore 117576Singapore

Metallic materials have historic and served as critical enablers of human progress,wealth,and wellbeing over ***,the global demand for the development of environment-friendly and energy-saving technology has been increasing,with the aim to support the sustainability of metallic ***-roll strip casting(TRC)is one of the most cutting-edge technologies and a near-net-shape manufacturing method in the steel industry,which conforms to the green fabrication trend of next-generation high-performance metallic *** utilizing the dominant characteristics of sub-rapid solidification,and integration of solidification,solid-state transformation,and deformation;TRC has become a meaningful way to deal with the most challenging issues in the processing of metallic materials,and made a significant contribution to materials ***,we review the TRC process of various metallic materials,including plain carbon steels,stainless steels,Fe-Si electrical steels,high-strength steels,clad steels,aluminum alloys,magnesium alloys,metallic glasses,and so *** paper offers an outlook of future opportunities for various advanced metallic materials development through the TRC process,and inspires more in-depth research.

关键词： twin-roll strip casting metallic materials steels alloys

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Multi-Objective Cooperative Salvo Attack Against Group Target

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Journal of Systems Science & Complexity 2018年第1期31卷 244-261页

作者： zeng jie DOU Lihua XIN Bin School of Automation State Key Laboratory of Intelligent Control and Decision of Complex SystemsBeijing Advanced Innovation Center for Intelligent Robots and Systems Beijing Institute of Technology

This paper proposes a solution for the problem of cooperative salvo attack of multiple cruise missiles against targets in a group. Synchronization of the arrival time of missiles to hit their common target, minimizing the time consumption of attack and maximizing the expected damage to group targets are taken into consideration simultaneously. These operational objectives result in a hierarchical mixed-variable optimization problem which includes two types of subproblems, namely the multi-objective missile-target assignment（MOMTA） problem at the upper level and the time-optimal coordinated path planning（TOCPP） problems at the lower level. In order to solve the challenging problem, a recently proposed coordinated path planning method is employed to solve the TOCPP problems to achieve the soonest salvo attack against each target. With the aim of finding a more competent solver for MOMTA, three state-of-the-art multi-objective optimization methods（MOMs）,namely NSGA-II, MOEA/D and DMOEA-εC, are adopted. Finally, a typical example is used to demonstrate the advantage of the proposed method. A simple rule-based method is also employed for comparison. Comparative results show that DMOEA-εC is the best choice among the three MOMs for solving the MOMTA problem. The combination of DMOEA-εC for MOMTA and the coordinated path planning method for TOCPP can generate obviously better salvo attack schemes than the rule-based method.

关键词： Coordinated path planning missile-target assignment multi-missile salvo attack multiobjective optimization

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Burnup analysis for the pebble-bed fluoride-salt-cooled high-temperature reactor based on the energy-dependent elastic scattering cross-sectional model

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Nuclear Science and Techniques 2018年第9期29卷 122-129页

作者： Zhi-Feng Li jie-Jin Cai Qin zeng Wen-jie zeng School of Electric Power South China University of Technology School of Nuclear Engineering Purdue University School of Nuclear Science and Technology University of South China

To carry out accurate burnup calculations for a pebble-bed fluoride-salt-cooled high-temperature reactor,the energy-dependent cross-sectional model based on the Doppler broadening rejection correction method has been proposed to develop the energy-dependent elastic scattering cross-sectional model. In this study, the Monte Carlo continuous energy code PSG2/Serpent was used to examine the difference between the constant cross-sectional model and the energy-dependent cross-sectional model during burnup. For the cases analyzed in this study,numerical simulations show that the multiplication coefficient was improved by hundreds pcm and ^(239)Pu concentration was improved by approximately 1–2% during burnup when the energy-dependent elastic scattering crosssectional model is considered.

关键词： PB-FHR Doppler broadening rejection correction Resonance elastic scattering PSG2/Serpent

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A joint mid-course and terminal course cooperative guidance law for multi-missile salvo attack

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Chinese Journal of Aeronautics 2018年第6期31卷 1311-1326页

作者： jie zeng Lihua DOU Bin XIN School of Automation Beijing Institute of Technology Beijing 100081 China State Key Laboratory of Intelligent Control and Decision of-Complex Systems Beijing 100081 China

Salvo attacking a surface target by multiple missiles is an effective tactic to enhance the lethality and penetrate the defense system. However, existing cooperative guidance laws in the midcourse or terminal course are not suitable for long-and medium-range missiles or stand-off attacking. Because the initial conditions of cooperative terminal guidance that are generally generated from the mid-course flight may not lead to a successful cooperative terminal guidance without proper mid-course flight adjustment. Meanwhile, cooperative guidance in the mid-course cannot solely guarantee the accuracy of a simultaneous arrival of multiple missiles. Therefore, a joint mid-course and terminal course cooperative guidance law is developed. By building a distinct leader-follower framework, this paper proposes an efficient coordinated Dubins path planning method to synchronize the arrival time of all engaged missiles in the mid-course flight. The planned flight can generate proper initial conditions for cooperative terminal guidance, and also benefit an earliest simultaneous arrival. In the terminal course, an existing cooperative proportional navigation guidance law guides all the engaged missiles to arrive at a target accurately and *** integrated guidance law for an intuitive application is summarized. Simulations demonstrate that the proposed method can generate fast and accurate salvo attack.

关键词： Cooperative systems Dubins path Mid-course flight Missile guidance Salvo attack

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Novel multi-objective optimization algorithm

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系统工程与电子技术：英文版 2014年第4期25卷 697-710页

作者： jie zeng Wei Nie College of Information Engineering Shenzhen University Modern Communication and Information Processing Key Laboratory Shenzhen University

Many multi-objective evolutionary algorithms(MOEAs)can converge to the Pareto optimal front and work well on two or three objectives, but they deteriorate when faced with manyobjective problems. Indicator-based MOEAs, which adopt various indicators to evaluate the fitness values(instead of the Paretodominance relation to select candidate solutions), have been regarded as promising schemes that yield more satisfactory results than well-known algorithms, such as non-dominated sorting genetic algorithm(NSGA-II) and strength Pareto evolutionary algorithm(SPEA2). However, they can suffer from having a slow convergence speed. This paper proposes a new indicatorbased multi-objective optimization algorithm, namely, the multiobjective shuffled frog leaping algorithm based on the ε indicator(ε-MOSFLA). This algorithm adopts a memetic meta-heuristic,namely, the SFLA, which is characterized by the powerful capability of global search and quick convergence as an evolutionary strategy and a simple and effective ε-indicator as a fitness assignment scheme to conduct the search procedure. Experimental results, in comparison with other representative indicator-based MOEAs and traditional Pareto-based MOEAs on several standard test problems with up to 50 objectives, show that ε-MOSFLA is the best algorithm for solving many-objective optimization problems in terms of the solution quality as well as the speed of convergence.

关键词： evolutionary algorithm multi-objective optimization shuffled frog leaping algorithm(SFLA) convergence

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Morphometric study confirms the presence of only Vatica mangachapoi on Hainan Island, China

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Journal of Forestry Research 2018年第3期29卷 636-643页

作者： Junjie Guo Shuaibin Shang jie zeng Research Institute of Tropical Forestry CAF

To date only one species of the genus Vatica Linn.(Dipterocarpaceae) has been identified, and a subspecies and three varieties have been reported on Hainan Island, China. However, it remained controversial whether the species was Vatica mangachapoi or a new species Vatica hainanensis, and whether the subspecies or varieties are taxonomically valid. We evaluated here morphometric variations of 133 trees collected from nine populations and herbarium specimens of Vatica spp. using 16 traits of leaf and fruit. Among these, leaf traits varied more within and among populations than did fruit traits. Four traits of ratios were more stable than directly-measured traits within and among populations. The ranges of lamina length, lamina width and height of maximum lamina width point were the greatest among the 16 traits, while number of lateral veins varied least among the 12 directly-measured traits. Measurements from all 9 populations overlapped for each morphological trait, and variation of each trait was continuous among both individuals and populations. The range of variation did not distinguish any specimen from V mangachapoi as described in the flora of Southeast Asia By cluster analysis, individuals of each population as wel as specimens of each variety formed no distinct clusters The published varieties thus were characterized by no distinguishing variations in comparison with the nine sampled populations. In conclusion, the new species V hainanensis as well as the subspecies and varieties were not supported by our comparisons, and only V. man gachapoi without any subspecies or varieties occurs on Hainan Island, China.

关键词： Vatica Linn. Vatica mangachapoi Morphological variability Cluster analysis Hainan Island

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Impacts of traffic accessibility on ecosystem services:An integrated spatial approach

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Journal of Geographical Sciences 2021年第12期31卷 1816-1836页

作者： CHEN Wanxu zeng Yuanyuan zeng jie Department of Geography School of Geography and Information EngineeringChina University of GeosciencesWuhan 430074China Research Center for Spatial Planning and Human-Environmental System Simulation China University of GeosciencesWuhan 430074China Guangdong Urban&Rural Planning and Design Institute CO. LTD.Guangzhou 510290China

The continuous degradation of ecosystem services is an important challenge faced by the *** in transportation infrastructure have had substantial impacts on economic development and ecosystem *** the influence of traffic accessibility on ecosystem services can delay or stop their deterioration;however,studies on its impact are *** study addresses this gap by analysing the impact of traffic accessibility on ecosystem services using an integrated spatial regression approach based on an evaluation of the ecosystem services value(ESV)and traffic accessibility in the Middle Reaches of the Yangtze River Urban Agglomeration(MRYRUA)in *** results indicated that the ESV in the MRYRUA continuously decreased during the study period,and the average ESV in plain areas,areas surrounding the core cities,and areas along the main traffic routes was significantly lower than that in areas along the Yangtze River and the surrounding mountainous *** accessibility continued to increase during the study period,and the high-value areas centred on Wuhan,Changsha,Nanchang,and Yichang were radially *** global bivariate spatial autocorrelation coefficient between the average ESV and traffic accessibility was *** average ESV and traffic accessibility exhibited significant spatial dependence and spatial *** regression also proved that there was a negative association between the average ESV and traffic accessibility,and scale effects were *** findings of this study have important policy implications for future ecological protection and transportation planning.

关键词： ecosystem services value traffic accessibility spatial regression Middle Reaches of the Yangtze River Urban Agglomeration China

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Amino acid profiles and protein quality of Siberian apricot(Prunus sibirica L.)kernels from Inner Mongolia

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Journal of Forestry Research 2020年第4期31卷 1391-1397页

作者： Mingyu Yin Tana Wuyun Zhongmao Jiang jie zeng State Key Laboratory of Tree Genetics and Breeding Nontimber Forestry Research and Development CenterPaulownia Research and Development Center of ChinaState Forestry AdministrationKey Laboratory of Non-timber Forest Germplasm Enhancement and Utilization of State Forestry AdministrationChinese Academy of ForestryZhengzhou 450003HenanPeople’s Republic of China Research Institute of Tropical Forestry Chinese Academy of ForestryGuangzhou 510520GuangdongPeople’s Republic of China

Siberian apricot(Prunus sibirica L.)is a traditional nut tree species in East Asia and Siberia and is a possible contribution to healthy ***,it has attracted little research attention and information on the nutritional value of its kernel is *** this study,the profile,nutritional value and variation of amino acids were investigated in eight *** kernels contained29×10-2 g/g protein and were rich in glutamic acid(26.5%),aspartic acid(11.3%)and arginine(10.1%).They showed higher essential amino acids(EAA)than similar protein values for *** variation coefficients of amino acids ranged from 3.8 to 43.7%,and the levels of seven amino acids were significantly different among the eight *** proportion of essential amino acids to total amino acids and amino acid score were also quite *** was negatively correlated with some amino acids and protein quality *** conclusion,there were two superior provenances(Wanjiagou and Horinger County)with high EAA contents and protein quality,and could be used in the large-scale development of this species.

关键词： Prunus sibirica L. Amino acids Nutritional value Diversity

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