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Conceptual design and control method for a noncontact annular electromagnetic stabilized satellite platform

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Chinese Journal of Aeronautics 2024年第1期37卷 256-270页

作者： he LIAO Daixin WANG Yuan REN Weijie WANG Institute of Astronautics Nanjing University of Aeronautics and AstronauticsNanjing 211106China Department of Basic Course Space Engineering UniversityHuairou DistrictBeijing 101416China

Disturbance-Free Payload(DFP)spacecraft can meet the requirements of ultra-high attitude pointing accuracy and stability for future space missions.However,as the main control actuators of DFP spacecraft,Linear Non-Contact Lorentz Actuators(LNCLAs)have control output problems with six-degree-of-freedom coupling and nonlinear effects,which will affect the attitude control performance of DFP spacecraft.To solve this problem,a novel concept for Non-Contact Annular Electromagnetic Stabilized Satellite Platform(NCAESSP)is proposed in this study.The concept is centered on replacing the LNCLAs with a non-contact annular electromagnetic actuator to solve the two problems mentioned above.Furthermore,for the different control requirements of the payload module and the support module of the NCAESSP,a high-precision attitude controller based on the robust model matching method and a dual quaternion-based adaptive sliding mode controller are proposed.Additionally,the simulation results verify the feasibility and effectiveness of the proposed approach.

关键词： Disturbance-free payload Robust model matching Dual quaternion Sliding mode control Collision avoidance

Experimental distillation of tripartite quantum steering with an optimal local filtering operation

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Photonics Research 2024年第3期12卷 552-562页

作者： QIAN-XI ZHANG XIAO-XU FANG he LU School of Physics State Key Laboratory of Crystal MaterialsShandong UniversityJinan 250100China Shenzhen Research Institute of Shandong University Shenzhen 518057China

Multipartite Einstein-Podolsky-Rosen(EPR)steering admits multipartite entanglement in the presence of uncharacterized verifiers,enabling practical applications in semi-device-independent protocols.Such applications generally require stronger steerability,while the unavoidable noise weakens steerability and consequently degrades the performance of quantum information processing.here,we propose the local filtering operation that can maximally distill genuine tripartite EPR steering from N copies of three-qubit generalized Greenberger-Horne-Zeilinger states,in the context of two semi-device-independent scenarios.The optimal filtering operation is determined by the maximization of assemblage fidelity.Analytical and numerical results indicate the advantage of the proposed filtering operation when N is finite and the steerability of initial assemblages is weak.Experimentally,a proof-of-principle demonstration of two-copy distillation is realized with the optical system.The advantage of the optimal local filtering operation is confirmed by the distilled assemblage in terms of higher assemblage fidelity with perfectly genuine tripartite steerable assemblages,as well as the greater violation of the inequality to witness genuine tripartite steerable assemblages.Our results benefit the distillation of multipartite EPR steering in practice,where the number of copies of initial assemblages is generally finite.

关键词： filtering distillation optimal

OIP5 Interacts with NCK2 to Mediate Human Spermatogonial Stem Cell Self-Renewal and Apoptosis through Cell Cyclins and Cycle Progression and Its Abnormality Is Correlated with Male Infertility

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Research 2024年第1期2023卷 455-469页

作者： Yinghong Cui Wei Chen Li Du Zuping he The Key Laboratory of Model Animals and Stem Cell Biology in Hunan Province The Research Center of Reproduction and Translational Medicine of Hunan ProvinceHunan Normal University School of MedicineChangsha 410013HunanChina

Spermatogonial stem cells(SSCs)have important applications in both reproduction and regenerative medicine.Nevertheless,specific genes and signaling transduction pathways in mediating fate decisions of human SSCs remain elusive.here,we have demonstrated for the first time that OIP5(Opa interacting protein 5)controlled the self-renewal and apoptosis of human SSCs.RNA sequencing identified that NCK2 was a target for OIP5 in human SSCs,and interestingly,OIP5 could interact with NCK2 as shown by Co-IP(co-immunoprecipitation),IP-MS(mass spectrometry),and GST pulldown assays.NCK2 silencing decreased human SSC proliferation and DNA synthesis but enhanced their apoptosis.Notably,NCK2 knockdown reversed the influence of OIP5 overexpression on human SSCs.Moreover,OIP5 inhibition decreased the numbers of human SSCs at S and G2/M phases,while the levels of numerous cell cycle proteins,including cyclins A2,B1,D1,E1 and H,especially cyclin D1,were remarkably reduced.Significantly,whole-exome sequencing of 777 patients with nonobstructive azoospermia(NOA)revealed 54 singlenucleotide polymorphism mutations of the OIP5 gene(6.95%),while the level of OIP5 protein was obviously lower in testes of NOA patients compared to fertile men.Collectively,these results implicate that OIP5 interacts with NCK2 to modulate human SSC self-renewal and apoptosis via cell cyclins and cell cycle progression and that its mutation and/or lower expression is correlated with azoospermia.As such,this study offers novel insights into molecular mechanisms underlying the fate determinations of human SSCs and the pathogenesis of NOA,and it provides new targets for treating male infertility.

关键词： OIP5 Apoptosis reversed

Whispering-gallery-mode barcode-based broadband sub-femtometer-resolution spectroscopy with an electro-optic frequency comb

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Advanced Photonics 2024年第1期6卷 115-125页

作者： Bingxin Xu Yangyang Wan Xinyu Fan Zuyuan he Shanghai Jiao Tong University State Key Laboratory of Advanced Optical Communication Systems and NetworksDepartment of Electronic EngineeringShanghaiChina Max-Planck Institute of Quantum Optics Hans-Kopfermann-Straûe 185748 GarchingGermany

Spectroscopy is the basic tool for studying molecular physics and realizing biochemical sensing.However,it is challenging to realize sub-femtometer resolution spectroscopy over broad bandwidth.Broadband and high-resolution spectroscopy with calibrated optical frequency is demonstrated by bridging the fields of speckle pattern and electro-optic frequency comb.A wavemeter based on a whispering-gallery-mode barcode is proposed to link the frequencies of a probe continuous-wave laser and an ultrastable laser.The ultrafine electro-optic comb lines are generated from the probe laser to record spectrum of sample with sub-femtometer resolution.Measurement bandwidth is a thousandfold broader than comb bandwidth,by sequentially tuning the probe laser while its wavelength is determined.This approach fully exploits the advantages of two fields to realize 0.8-fm resolution with a fiber laser and 80-nm bandwidth with an external cavity diode laser.The spectroscopic measurements of an ultrahigh Q-factor cavity and gas molecular absorption are experimentally demonstrated.The compact system,predominantly constituted by few-gigahertz electronics and telecommunication components,shows enormous potential for practical spectroscopic applications.

关键词： frequency comb reconstructive wavemeter spectroscopy

Will fuel switching ever happened in China’s thermal power sector?The rule of carbon market design

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Frontiers of Engineering Management 2024年第2期11卷 207-230页

作者： Anqi he Huarong PENG Wuhan University Institute for International Studies Wuhan UniversityWuhan 430072China Climate Change and Energy Economics Study Center Economics and Management SchoolWuhan UniversityWuhan 430000China Collaborative Innovation Center for Emissions Trading System by Ministry of Education and Hubei Provincial Government Hubei University of EconomicsWuhan 430200China

o assess the effectiveness of China’s emissions trading scheme(ETS)in facilitating energy structure optimization,we constructed a fuel-switching model utilizing data from 1067 generating units under the Chinese ETS framework.The model simulates the fuel-switching price in China’s thermal power sector,taking into account various allowance allocation strategies.The results show the following:1)Thermal power plants will transition from coal to gas if the current ETS auction rate surpasses 26%.2)Furthermore,in scenarios where the ETS operates independently,a transition will occur if the carbon allowance market is entirely auction-based and the carbon price attains 119.50 USD/tCO_(2).3)In a collaborative scenario involving both the ETS and a gas feed-in tariff subsidy,a carbon price of 9.39 USD/tCO_(2)will effect a transition from coal to gas,provided both the auction ratio and subsidy price are maximized.

关键词： ETS thermal power plant fuel switching allowance allocation method feed-in tariff subsidy

Interaction of yttrium barrier and calcium-rich phase on production and properties of WC precursor powders and alloys

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Journal of Rare Earths 2024年第1期42卷 228-236,I0008页

作者： Wen he Dunqiang Tan Zhiqiang Yi Zhiqiang Liu School of Materials Science and Engineering Nanchang UniversityNanchang330031China Instrumental Analysis Center of Nanchang Hangkong University Nanchang330063China

In order to reduce or eliminate the adverse effects of calcium impurity,the interaction of Ca and rare earth Y co-doping on the preparation of WC-Co cemented carbides was investigated.X-ray diffraction,scanning electron microscopy and transmission electron microscopy were employed to analyze the phase compositions,particle sizes and morphologies of them,respectively.The results show that the second type of"yttrium barrier effect"is observed and the adverse influence of Ca-rich phase on tungsten powder can be eliminated by it.The flexural strength and fracture toughness of YG6-0.01%Ca+0.09%Y alloy are 2199.5 MPa and 11.49 MPa·m^(1/2),showing improvement of 6.5% and 2.7% compared to YG6 alloy,respectively.The evolutions of Ca-rich phase and Y-rich phase at the every alloy preparation stage of WO_(3),W,WC and cemented carbides are obtained.Furthermore,the strengthening mechanism of WC-Co cemented carbide with co-addition of Ca and Y is proposed.

关键词： Yttrium barrier effect Ca-rich phase WC-Co cemented Carbide Microstructures Mechanisms Rare earths

In-situ powder mixing for laser-based directed energy deposition of functionally graded materials

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Advances in Manufacturing 2024年第1期12卷 150-166页

作者： Ji-Peng Chen Shou-Chun Xie he Huang School of Mechanical and Electronic Engineering Nanjing Forestry UniversityNanjing210037People’s Republic of China Nanjing Huirui Photoelectric Technology Co. LtdNanjing211121People’s Republic of China

The mixing of powders is a highly relevant field under additive manufacturing,however,it has attracted limited interest to date.The in-situ mixing of various powders remains a significant challenge.This paper proposes a new method utilizing a static mixer for the in-situ mixing of multiple powders through the laser-based directed energy deposition(DED)of functionally graded materials.Firstly,a powder-mixing experimental platform was established;WC and 316L powders were selected for the mixing experiments.Secondly,scanning electron microscopy,energy dispersive spectroscopy,and image processing were used to visually evaluate the homogeneity and proportion of the in-situ mixed powder.Furthermore,powder-mixing simulations were conducted to determine the powder-mixing mechanism.In the simulations,a powder carrier gas flow field and particle mixing were employed.Finally,a WC/316L metal matrix composite sample was produced using laser-based DED to verify the application potential of the static mixer.It was found that the static mixer could adjust the powder ratio online,and a response time of 1–2 s should be considered when adjusting the ratio of the mixed powder.A feasible approach for in-situ powder mixing for laser-based DED was demonstrated and investigated,creating the basis for functionally graded materials.

关键词： Laser Deposition Static mixer Powder mixing Functionally graded materials

Monitoring and evaluation of the water quality of the Lower Neches River, Texas, USA

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Water Science and Engineering 2024年第1期17卷 21-32页

作者： Qin Qian Mengjie he Frank Sun Xinyu Liu Department of Civil and Environmental Engineering Lamar UniversityBeaumontTX 77710USA Department of Industry Engineering Lamar UniversityBeaumontTX 77710USA Department of Computer Science Lamar UniversityBeaumontTX 77710USA

Increasing bacteria levels in the Lower Neches River caused by Hurricane Harvey has been of a serious concern.This study is to analyze the historical water sampling measurements and real-time water quality data collected with wireless sensors to monitor and evaluate water quality under different hydrological and hydraulic conditions.The statistical and Pearson correlation analysis on historical water samples determines that alkalinity,chloride,hardness,conductivity,and pH are highly correlated,and they decrease with increasing flow rate due to dilution.The flow rate has positive correlations with Escherichia coli,total suspended solids,and turbidity,which demonstrates that runoff is one of the causes of the elevated bacteria and sediment loadings in the river.The correlation between E.coli and turbidity indicates that turbidity greater than 45 nephelometric turbidity units in the Neches River can serve as a proxy for E.coli to indicate the bacterial outbreak.A series of statistical tools and an innovative two-layer data smoothing filter are developed to detect outliers,fill missing values,and filter spikes of the sensor measurements.The correlation analysis on the sensor data illustrates that the elevated sediment/bacteria/algae in the river is either caused by the first flush rain and heavy rain events in December to March or practices of land use and land cover.Therefore,utilizing sensor measurements along with rainfall and discharge data is recommended to monitor and evaluate water quality,then in turn to provide early alerts on water resources management decisions.

关键词： Water quality Pearson correlation analysis Lower Neches River YSI wireless sensors Non-point pollution

Accelerated Primal-Dual Projection Neurodynamic Approach With Time Scaling for Linear and Set Constrained Convex Optimization Problems

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IEEE/CAA Journal of Automatica Sinica 2024年第6期11卷 1485-1498页

作者： You Zhao Xing he Mingliang Zhou Tingwen Huang Chongqing Key Laboratory of Nonlinear Circuits and Intelligent Information Processing College of Electronic and Information EngineeringSouthwest UniversityChongqing 400715China School of Computer Science Chongqing UniversityChongqing 400044China Department of Mathematics Texas A&M University at QatarDoha 23874Qatar IEEE

The Nesterov accelerated dynamical approach serves as an essential tool for addressing convex optimization problems with accelerated convergence rates.Most previous studies in this field have primarily concentrated on unconstrained smooth con-vex optimization problems.In this paper,on the basis of primal-dual dynamical approach,Nesterov accelerated dynamical approach,projection operator and directional gradient,we present two accelerated primal-dual projection neurodynamic approaches with time scaling to address convex optimization problems with smooth and nonsmooth objective functions subject to linear and set constraints,which consist of a second-order ODE(ordinary differential equation)or differential conclusion system for the primal variables and a first-order ODE for the dual vari-ables.By satisfying specific conditions for time scaling,we demonstrate that the proposed approaches have a faster conver-gence rate.This only requires assuming convexity of the objective function.We validate the effectiveness of our proposed two accel-erated primal-dual projection neurodynamic approaches through numerical experiments.

关键词： Accelerated projection neurodynamic approach lin-ear and set constraints projection operators smooth and nonsmooth convex optimization time scaling.