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Improved IMM algorithm based on support vector regression for UAV tracking

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Journal of Systems Engineering and Electronics 2022年第4期33卷 867-876页

作者： Zeng Yuan LU Wenbin YU Bo TAO Shifei ZHOU Haosu CHEN Yu Shanghai Spaceflight Electronic and Communication Equipment Research Institute Shanghai 201109China Science and Technology on Near-Surface Detection Laboratory Wuxi 214035China School of Electronic and Optical Engineering Nanjing University of Science and TechnologyNanjing 210094China

With the development of technology, the relevant performance of unmanned aerial vehicles(UAVs) has been greatly improved, and various highly maneuverable UAVs have been developed, which puts forward higher requirements on target tracking technology. Strong maneuvering refers to relatively instantaneous and dramatic changes in target acceleration or movement patterns, as well as continuous changes in speed,angle, and acceleration. However, the traditional UAV tracking algorithm model has poor adaptability and large amount of calculation. This paper applies support vector regression(SVR)to the interacting multiple model(IMM) algorithm. The simulation results show that the improved algorithm has higher tracking accuracy for highly maneuverable targets than the original algorithm, and can adjust parameters adaptively, making it more adaptable.

关键词： interacting multiple model(IMM)filter constant acceleration(CA) unmanned aerial vehicle(UAV) support vector regression(SVR)

Clustering and Resource Allocation Strategy for D2D Multicast Networks with Machine Learning Approaches

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China Communications 2021年第1期18卷 196-211页

作者： Fan Jiang Lan Zhang Changyin Sun Zeng Yuan Xi’an University of Posts and Telecommunications Xi’an 710121China Shaanxi Key Laboratory of Telecommunications and Information Networks and Security Xi’an 710121China

In this paper,the clustering and resource allocation problem in device-to-device(D2D)multicast transmission underlay cellular networks are investigated.For the sake of classifying D2D users into different D2D multicast clusters,a hybrid intelligent clustering strategy(HICS)based on unsupervised machine learning is proposed first.By maximizing the total energy efficiency of D2D multicast clusters,a joint resource allocation scheme is then presented.More specifically,the energy efficiency optimization problem is constructed under the quality of service(QoS)constraints.Since the joint optimization problem is non-convex,we transform the original problem into a mixed-integer programming problem according to the Dinkelbach algorithm.Furthermore,to avoid the high computational complexity inherent in the traditional resource allocation problem,a Q-Learning based joint resource allocation and power control algorithm is proposed.Numerical results reveal that the proposed algorithm achieves better energy efficiency in terms of throughput per energy consumption.

关键词： device-to-device multicast communication clustering energy efficiency resource allocation Q-Learning

Numerical simulation of hypersonic thermochemical nonequilibrium flows using nonlinear coupled constitutive relations

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Chinese Journal of Aeronautics 2023年第3期36卷 63-79页

作者： Shuhua zeng Zhenyu yuan Wenwen ZHAO Weifang CHEN School of Aeronautics and Astronautics Zhejiang UniversityHangzhou 310027China School of Energy and Power Engineering Nanjing University of Science and TechnologyNanjing 210094China

To predict aeroheating performance of hypersonic vehicles accurately in thermochemical nonequilibrium flows accompanied by rarefaction effect,a Nonlinear Coupled Constitutive Relations(NCCR)model coupled with Gupta’s chemical models and Park’s two-temperature model is firstly proposed in this paper.Three typical cases are intensively investigated for further validation,including hypersonic flows over a two-dimensional cylinder,a RAM-C II flight vehicle and a type HTV-2 flight vehicle.The results predicted by NCCR solution,such as heat flux coefficient and electron number densities,are in better agreement with those of direct simulation Monte Carlo or flight data than Navier-Stokes equations,especially in the extremely nonequilibrium regions,which indicates the potential of the newly-developed solution to capture both thermochemical and rarefied nonequilibrium effects.The comparisons between the present solver and NCCR model without a two-temperature model are also conducted to demonstrate the significance of vibrational energy source term in the accurate simulation of high-Mach flows.

关键词： Hypersonic flow Nonlinear coupled constitutive relations Rarefied gas Thermochemical nonequilibrium effect Vibrational excitation

Optimal Coordinated Bidding Strategy of Wind and Solar System with Energy Storage in Day-ahead Market

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Journal of Modern Power Systems and Clean Energy 2022年第1期10卷 192-203页

作者： Yinping Yang Chao Qin yuan zeng Chengshan Wang School of Electrical and Information Engineering Tianjin UniversityTianjin 300072China

Although wind and solar power is the major reliable renewable energy sources used in power grids,the fluctuation and unpredictability of these renewable energy sources require the use of ancillary services,thereby increasing the integration cost.This study proposes a wind,solar,and pumped-storage cooperative(WSPC)model that can be applied to large-scale systems connected to dispersed renewable energy sources.This model provides an optimized coordinated bidding strategy in the day-ahead market,along with a method to facilitate revenue distribution among participating members.This model takes advantage of the natural complementary characteristics of wind and solar power while using pumped storage to adjust the total output power.In the coordinated bidding strategy,a proportion of the energies is provided as firm power,which can lower the ancillary service requirement.Moreover,a multi-period firm power-providing mode is adopted to reflect the wind-solar output characteristics of each period accurately.The duration of each period is selected as a variable to accommodate seasonal characteristics.This ensures that the provision of firm power can maintain a high proportion under varied connected ratios of wind-solar,thereby obtaining higher revenue.By using the revenue distribution method,the short-term influencing factors of the cooperative model are considered to provide the economic characteristics of wind farms and photovoltaic stations.In this way,revenue distribution can be fairly realized among the participating members.Finally,the effectiveness and economy of the proposed model are validated based on actual data obtained from the power grid in California,USA.

关键词： Wind energy solar energy energy storage energy resources power system economics

Box-Behnken experimental design for optimizing process parameters in carbonate-promoted direct thiophene carboxylation reaction with carbon dioxide

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Chinese Journal of Chemical Engineering 2022年第10期50卷 222-234页

作者： Qingjun Zhang Youguang Ma Xigang yuan Aiwu zeng State Key Laboratory of Chemical Engineering School of Chemical Engineering and TechnologyTianjin UniversityTianjin 300350China Chemical Engineering Research Center Collaborative Innovative Center of Chemical Science and Engineering(Tianjin)Tianjin 300350China

A feasible synthesis route is developed for achieving the direct carboxylation of thiophene and CO_(2) in a relatively mild solvent-free carboxylate-assisted carbonate(semi)molten state.The effects of reaction factors on the carboxylate yield are investigated in the preliminary screening experiments,and the phase behavior analysis of the reaction medium is detected through the thermal characterization analysis of insitu high temperature X-ray diffraction measurement(in-situ XRD).The application of response surface methodology(RSM)based on the Box-Behnken design(BBD)is conducted to investigate the effect of the reaction parameters,such as reaction temperatu re,carbonate proportion,CO_(2) pressure and thiophene amount,on the product yield.The regressed second-order polynomial model equation well correlates all the independent variables.The analysis of variance(ANOVA)results reveal that the quadratic effect of reaction temperature is the most effective parameter in this carboxylation reaction owing to it’s the highest contribution to the sum of square(30.18%).The optimum reaction conditions for maximum product yield are the reaction temperature of 287℃,carbonate proportion of 32.20%,CO_(2) pressure of 1.0MPa and thiophene amount of 9.35 mmol.Operating under these selected experimental conditions,a high product yield(50.98%)can be achieved.

关键词： Carboxylation Solvent-free medium Molten salt Optimization Response surfacemethodology

Current and emerging immunotherapeutic approaches for biliary tract cancers

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Hepatobiliary & Pancreatic Diseases International 2022年第5期21卷 440-449页

作者： Zhen-Gang yuan Tian-Mei zeng Chen-Jie Tao Department of Oncology Eastern Hepatobiliary Surgery HospitalSecond Military Medical University(Navy Medical University)Shanghai 200438China

Background:Biliary tract cancers(BTCs)comprise a heterogeneous group of aggressive malignancies with unfavorable prognoses.The benefit of chemotherapy seems to have reached a bottleneck and,therefore,new effective therapeutic strategies for advanced BTCs are needed.Molecularly targeted therapies in selected patients are rapidly changing the situation.However,the low frequency of specific driver alterations in BTCs limits their wide application.Recently,immunotherapeutic approaches are also under active investigation in BTCs,but the role of immunotherapy in BTCs remains controversial.Data sources:Pub Med,Web of Science,and meeting resources were searched for relevant articles published from January 2017 to May 2022.The search aimed to identify current and emerging immunotherapeutic approaches for BTCs.Information on clinical trials was obtained from https://clinicaltrials.gov/and http://***/.Results:Immunotherapy in BTC patients is currently under investigation,and most of the investigations focused on the application of immune checkpoint inhibitors(ICIs).However,only a subgroup of BTCs with microsatellite-instability high(MSI-H)/DNA mismatch repair-deficient(d MMR)or tumor mutational burden-high(TMB-H)benefit from monotherapy of ICIs,and limited activity was observed in the second or subsequent settings.Nevertheless,promising results come from studies of ICIs in combination with other therapeutic approaches,including chemotherapy,in advanced BTCs,with a moderate toxicity profile.Recent studies demonstrated that compared to GEMCIS alone,durvalumab plus GEMCIS significantly improved patient survival(TOPAZ-1 trial)and that ICIs-combined chemoimmunotherapy is poised to become a new frontline therapy option,regardless of TMB and MMR/MSI status.Adoptive cell therapy and peptide-or dendritic-based cancer vaccines are other immunotherapeutic options that are being studied in BTCs.Numerous biomarkers have been investigated to define their predictive role in response to ICIs,but no predictive biomarker has been validated,e

关键词： Biliary tract cancer Cholangiocarcinoma Gallbladder cancer Immunotherapy Immune checkpoint inhibitors

Mercury accumulation and dynamics in montane forests along an elevation gradient in Southwest China

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Journal of Environmental Sciences 2022年第9期34卷 1-10页

作者： Shufang zeng Xun Wang Wei yuan Ji Luo Dingyong Wang College of Resources and Environment Southwest UniversityChongqing 400715China State Key Laboratory of Environmental Geochemistry Institute of GeochemistryChinese Academy of SciencesGuiyang 550081China Key Laboratory of Mountain Surface Processes and Ecological Regulation Institute of Mountain Hazards and EnvironmentChinese Academy of Sciences&Ministry of Water ConservancyChengdu 610041China

Understanding atmospheric mercury(Hg) accumulation in remote montane forests is critical to assess the Hg ecological risk to wildlife and human health. To quantify impacts of vegetation, climatic and topographic factors on Hg accumulation in montane forests, we assessed the Hg distribution and stoichiometric relations among Hg, carbon(C), and nitrogen(N) in four forest types along the elevation of Mt. Gongga. Our results show that Hg concentration in plant tissues follows the descending order of litter > leaf, bark > root > branch > bole wood, indicating the importance of atmospheric Hg uptake by foliage for Hg accumulation in plants. The foliar Hg/C(from 237.0 ± 171.4 to 56.8 ± 27.7 μg/kg) and Hg/N(from 7.5 ± 3.9 to 2.5 ± 1.2 mg/kg) both decrease along the elevation. These elevation gradients are caused by the heterogeneity of vegetation uptake of atmospheric Hg and the variation of atmospheric Hg ° concentrations at different altitudes. Organic soil Hg accumulation is controlled by forest types, topographic and climatic factors, with the highest concentration in the mixed forest(244.9 ± 55.7 μg/kg) and the lowest value in the alpine forest(151.9 ±44.5 μg/kg). Further analysis suggests that soil Hg is positively correlated to C( r^(2) = 0.66) and N( r^(2) = 0.57), and Hg/C and Hg/N both increase with the soil depth. These stoichiometric relations highlight the combined effects from environmental and climatic factors which mediating legacy Hg accumulation and selective Hg absorption during processes of organic soil mineralization.

关键词： Mercury deposition Montane forest Mercury accumulation Climate impact

Sol-gel approach to low-temperature synthesis of single-phase metastable La_(2)Ga_(3)O_(7.5) melilite with enhanced grain-boundary oxide ionic conductivity via a kinetically favorable mechanism

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Journal of Advanced Ceramics 2022年第10期11卷 1613-1625页

作者： yuan ZHANG Longfei ZHAO Zhupeng YE Yanwei zeng College of Materials Science and Engineering Nanjing Tech UniversityNanjing 211816China

Starting with the stoichiometric and highly homogeneous gel-precursor,single-phase metastable melilite La_(2)Ga_(3)O_(7.5),as the end-member of solid solution La_(1+x)Sr_(1−x)Ga_(3)O_(7+x/2)(0≤x≤1),has been synthesized by solid-state reaction at 700℃ for 2 h via a kinetically favorable mechanism and characterized by X-ray diffraction(XRD),Raman,X-ray photoelectron spectroscopy(XPS),field emission scanning electron microscopy(FESEM),transmission electron microscopy(TEM),AC impedance spectroscopy,etc.It has been revealed that the as-synthesized melilite La_(2)Ga_(3)O_(7.5) shows an orthorhombic symmetry with crystal cell parameters a=11.4690(1)A,b=11.2825(4)A,and c=10.3735(4)A,while has more Raman active modes than LaSrGa_(3)O_(7) with a tetragonal structure,which was also synthesized under the same conditions for comparison,but tends to slowly decompose into perovskite LaGaO_(3) and Ga2O_(3) when annealed at 700℃ for over 20 h driven by its meta-stability.Moreover,the metastable La2Ga3O7.5 shows a higher XPS binding energy for the excess oxide ions in the crystal structure than those at normal lattice sites.Its intrinsic grain oxide ion conductivity can reach as high as 0.04 and 0.51 mS·cm^(-1) at 550 and 700℃,respectively,characterized by a simple Arrhenius relationship ln(σT)-1/T with invariable activation energy,E_(a)=1.22 eV,over the temperature range from 300 to 700℃,along with an apparent grain boundary conductivity that is about double that from the grains thanks to the clean grain boundaries.This paper provides a new strategic approach to the synthesis of complex oxides that may be of high performance but are difficultly achieved by the conventional ceramic method at high temperatures.

关键词： melilite La_(2)Ga_(3)O_(7.5) low temperature synthesis gel-precursor meta-stability kinetic mechanism

Biomanufacturing boosts the high-level development of economy and society

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Green Chemical Engineering 2023年第2期4卷 135-136页

作者： Chun Li An-Ping zeng Ying-Jin yuan Key Lab for Industrial Biocatalysis Ministry of EducationDepartment of Chemical EngineeringTsinghua UniversityBeijing100084China Center for Synthetic&Systems Biology Department of Chemical EngineeringTsinghua UniversityBeijing100084China Center of Synthetic Biology and Integrated Bioengineering School of EngineeringWestlake UniversityHangzhou310030China Frontiers Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering(Ministry of Education) Tianjin UniversityTianjin300072China School of Chemical Engineering and Technology Tianjin UniversityTianjin300072China

Global society requires new technologies for manufacturing essential chemicals for modern life that are decoupled from fossil fuels.Therefore,Green Chemical Engineering focuses on the areas of green and sustain-able d... 详细信息

关键词： boost attractive chemicals