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Novel TPN control algorithm for exoatmospheric intercept

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Journal of Systems Engineering and Electronics 2009年第6期20卷 1290-1295页

作者： Chen Lei zhang bing Coll. of Aerospace and Material Engineering National Univ. of Defense Technology Changsha 410073 P. R. China

A novel control algorithm with fixed pulse thrust, based on true proportional navigation（TPN）, is proposed for exoatmospheric *** to the TPN guidance law and pulse thrust characteristics, the principle of control command is presented, the control stability and precision are *** the help of the TPN guidance law, the algorithm can automatically modulate the turn-on time and duration of the thrust, which could effectively limit the impact of measure noise of the line-of-sight（LOS） angle and rate on the interception *** last, the number-theoretic method（NTM） is introduced to acquire the relation between control algorithm and miss-distance, even as it simulates the intercept process with initial state *** the reliability of the algorithm is demonstrated with the simulation result.

关键词： exoatmospheric intercept true proportional navigation pulse thrust control algorithm numbertheoretic method.

Risk assessment of erosive aggressiveness due to the condensation shock by numerical simulation

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Journal of Hydrodynamics 2022年第2期34卷 200-206页

作者： Wei zhang bing Zhu Science and Technology on Water Jet Propulsion Laboratory Marine Design and Research Institute of ChinaShanghai200011China School of Energy and Power Engineering University of Shanghai for Science and TechnologyShanghai200093China

Cavitation is,for the engineering areas such as fluid machinery and ship propulsion,a known source of *** erosion damage due to cavitation bubble collapse can lead to extreme failure events,implying the replacement of a ship propeller or a turbine in a hydropower plant,all of which are very costly *** dynamics of cavitation hydraulic structure is of great importance for cavitation *** a result,the blade surface endures some extremely high stresses,which lead to the cause of *** major mechanisms,re-entrant jet as well as condensation shock,are known to such transient cavitating *** the present work we study the latter since less has been reported for the erosion caused by such an unsteady cavitating *** adopted an energy transportation equation based method,combined with a collapse event detection strategy,to carry out numerical erosion risk assessment for erosive aggressiveness due to the condensation *** with the paint test,our result shows good agreement in the erosive *** further discussed the hydrodynamics of the related flow structures.

关键词： Condensation shock numerical simulation cavitation erosion

Hamilton-Souplet-zhang's gradient estimates for two weighted nonlinear parabolic equations

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Applied Mathematics(A Journal of Chinese Universities) 2017年第3期32卷 353-364页

作者： MA bing-qing HUANG Guang-yue Department of Mathematics Henan Normal University Xinxiang 453007 China

In this paper, we consider gradient estimates for positive solutions to the following weighted nonlinear parabolic equations on a complete smooth metric measure space with only Bakry-Émery Ricci tensor bounded below: One is $${u_t} = {\Delta _f}u + au\log u + bu$$ with a, b two real constants, and another is $${u_t} = {\Delta _f}u + \lambda {u^\alpha }$$ with λ, α two real constants. We obtain local Hamilton-Souplet-zhang type gradient estimates for the above two nonlinear parabolic equations. In particular, our estimates do not depend on any assumption on f.

关键词： Hamilton’s gradient estimate Souplet-zhang’s gradient estimate weighted nonlinear parabolic equation Bakry-Émery Ricci tensor

Motivational interviewing in postoperative rehabilitation and chronic disease management: Current findings and future research directions

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World Journal of Psychiatry 2025年第1期15卷 26-31页

作者： bing-Ren zhang Xiao Yang Affiliated Hospital(School of Clinical Medicine) Hangzhou Normal UniversityHangzhou 311121Zhejiang ProvinceChina Mental Health Education and Counseling Center Hangzhou Normal UniversityHangzhou 311121Zhejiang ProvinceChina

This editorial highlights a recently published study examining the effectiveness of music therapy combined with motivational interviewing(MI)in addressing an-xiety and depression among young and middle-aged patients following percuta-neous coronary *** further explores existing evidence and potential future research directions for MI in postoperative rehabilitation and chronic disease *** aims to facilitate behavioral change and promote healthier lifestyles by fostering a trusting relationship with patients and enhan-cing intrinsic *** has demonstrated its effectiveness in posto-perative recovery for oncological surgery,stroke,organ transplants,and gastroin-testinal procedures,as well as in managing chronic conditions such as diabetes,obesity,and periodontal *** approach is patient-centered,adaptable,cost-effective,and easily replicable,though its limitations include reliance on the therapist’s expertise,variability in individual responses,and insufficient long-term follow-up *** research could focus on developing individualized and precise intervention models,exploring applications in digital health management,and confirming long-term outcomes to provide more compre-hensive support for patient rehabilitation.

关键词： Chronic disease management Motivational interviewing Patient-centered Postoperative rehabilitation Treatment adherence

When and How Plate Tectonics Began?

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Journal of Earth Science 2023年第4期34卷 1302-1303页

作者： Shao-bing zhang School of Earth and Space Sciences University of Science and Technology of ChinaHefei 230026China

Plate tectonics is the most important discovery in Earth Science in the 20th Century and is the core theory of Solid Earth Science. It describes that the Earth’ s lithosphere is divided into several plates that slide on top of the asthenosphere and move relative to each other along divergent, convergent, and transform plate boundaries. From a physical point of view.

关键词： Earth divergent tectonics

Integrated Extrusion-Shear Forming Process of the Solid-State Recycled AZ80 Magnesium Alloy via Hot Press Sintering

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Acta Metallurgica Sinica(English Letters) 2020年第3期33卷 351-361页

作者： bing Li Bugang Teng Baoting zhang School of Materials Science and Engineering Harbin Institute of TechnologyHarbin 150001China National Key Laboratory for Precision Hot Processing of Metals Harbin Institute of TechnologyHarbin 150001China

The consolidation recycled AZ80 billets were successfully fabricated through the cold press and hot press sintering of the AZ80 metal *** consolidation recycled billets sintered at 350℃present the comparable compressive properties and inferior tensile properties compared with the initial cast *** defects in the consolidation recycled billet were inclined to propagate along the bond interface between the metal chips during tension,which resulted in the inferior tensile properties of the recycled *** recycled billets were then subjected to the integrated extrusion-shear(ES) *** homogeneous finer dynamic recrystallization grains with an average grain size of 6 μm can be obtained in the shear deformation zone and extrusion sizing zone through integrated ES process at 300℃with an extrusion velocity of 0.6 mm/*** recycled billets after integrated ES forming process present rival tensile properties compared with the initial cast billets after integrated ES forming with the same extrusion parameters,which can be ascribed to that the integrated ES forming can nearly eliminate the defects through the severe compressive and shear *** solid-state recycling process through hot press sintering and subsequent integrated ES process can fabricate the consolidation recycled AZ80 rod,which demonstrates the comparable tensile properties with the cast-extrusion rod.

关键词： Solid-state recycling Hot press sintering Integrated extrusion-shear forming Metal chips Mechanical properties

Progress and perspective of high-voltage lithium cobalt oxide in lithium-ion batteries

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Journal of Energy Chemistry 2022年第11期31卷 283-308,I0008页

作者： Qian Wu bing zhang Yingying Lu State Key Laboratory of Chemical Engineering Institute of Pharmaceutical EngineeringCollege of Chemical and Biological EngineeringZhejiang UniversityHangzhou 310027ZhejiangChina ZJU-Hangzhou Global Scientific and Technological Innovation Center Hangzhou 311200ZhejiangChina

Lithium cobalt oxide(LiCoO_(2),LCO)dominates in 3C(computer,communication,and consumer)electronics-based batteries with the merits of extraordinary volumetric and gravimetric energy density,high-voltage plateau,and facile ***,the demand for lightweight and longer standby smart portable electronic products drives the development of the upper cut-off voltage of LCO-based batteries to further improve the energy ***,several challenges,including irreversible structural transformation,surface degradation,cobalt dissolution and oxygen evolution along with detrimental side reactions with the electrolyte remain with charging to a high cut-off voltage(>4.2 V ***/Li+),resulting in rapid capacity decay and safety *** on the degradation mechanisms and latest advances of the high-voltage LCO,this review summarizes modification strategies in view of the LCO structure,artificial interface design and electrolytes ***,many advanced characterization and monitoring techniques utilized to clarify the structural and interfacial evolution of LCO during charge/discharge process are critically ***,the perspectives in terms of integrating multiple modification strategies,applying gel and solid-state electrolytes,optimizing the recovery process and scalable production are presented.

关键词： LiCoO2 Electrode-electrolyte interface Lithium batteries Characterization techniques

Numerical research on adverse effect of muzzle flow formed by muzzle brake considering secondary combustion

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Defence Technology（防务技术） 2021年第4期17卷 1178-1189页

作者： Peng-fei Li Xiao-bing zhang School of Energy and Power Engineering Nanjing University of Science and TechnologyNanjing210094PR China

The simulation of the artillery interior and intermediate ballistics problem is performed to investigate the influence of a gas dynamics device,muzzle brake,on the muzzle hazard phenomena,such as flash and blast *** correlation of the chemical reactions with the characteristics of the muzzle flow field is analyzed by the simulation for a further understanding of the secondary combustion phenomenon of the muzzle *** novel structure of muzzle flow caused by the muzzle brake is presented by the simultaneous solution of the interior ballistics model and multi-species Navier-Stokes equations in order to analyze the influence of the muzzle brake structure on the chemical *** secondary combustion of the muzzle flow due to the oxygen-supplement chemical reactions is obtained by the chemical reaction kinetic *** interaction of the blast waves released from the muzzle brake is illustrated in detail and the mechanism of the formation of muzzle flash is *** research provides a reference for the studies on the suppression of the muzzle flash.

关键词： Muzzle flow Muzzle brake Secondary combustion Chemical reaction

Effect of Inlet and Outlet Manifolds on Regenerative Cooling in LOX/Methane Thrust Chambers

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Journal of Thermal Science 2021年第2期30卷 517-529页

作者： zhang Meng SUN bing SONG Jiawen School of Astronautics Beihang UniversityBeijing 100191China

Regenerative cooling is considered one of the most effective cooling methods used in liquid rocket engines and has been widely studied in recent *** the effect of the non-uniform flow in cooling channels caused by inlet and outlet manifolds did not attract much *** this paper,we carried out the coupled flow and heat transfer of combustion and regenerative cooling in a LOX/Methane (LOX means liquid oxygen) engine and compared the results with and without ***,three different configurations of the inlet and outlet manifolds were also *** results show that the parameters averaged in the circumferential direction are less affected by the ***,the existence of the manifolds will make the distribution of mass flow rate as well as wall temperature non-uniform along the circumferential *** addition,when the angles between inlet and outlet are 0°,90° and 180°,the maximum temperature difference along the circumference of throat increases by 90.1%,151.2% and 229.5%,respectively,compared with that without *** indicates that the larger the angle between inlet and outlet,the greater the non-uniformity of mass flow rate and wall temperature along the circumferential *** a result,extra thermal stress will be generated which could cause some negative effects on the rocket engines.

关键词： regenerative cooling conjugate heat transfer inlet and outlet manifolds non-uniform flow