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An algorithm for trajectory prediction of flight plan based on relative motion between positions

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Frontiers of Information Technology & Electronic Engineering 2018年第7期19卷 905-916页

作者： Yi LIN jian-wei zhang Hong LIU National Key Laboratory of Fundamental Science on Synthetic Vision Sichuan University National Key Laboratory of Air Traffic Control Automation System Technology Sichuan University

Traditional methods for plan path prediction have low accuracy and stability. In this paper, we propose a novel approach for plan path prediction based on relative motion between positions(RMBP) by mining historical flight trajectories. A probability statistical model is introduced to model the stochastic factors during the whole flight process. The model object is the sequence of velocity vectors in the three-dimensional Earth space. First, we model the moving trend of aircraft including the speed(constant, acceleration, or deceleration), yaw(left, right, or straight), and pitch(climb, descent, or cruise) using a hidden Markov model(HMM) under the restrictions of aircraft performance parameters. Then, several Gaussian mixture models(GMMs) are used to describe the conditional distribution of each moving trend. Once the models are built, machine learning algorithms are applied to obtain the optimal parameters of the model from the historical training data. After completing the learning process, the velocity vector sequence of the flight is predicted by the proposed model under the Bayesian framework, so that we can use kinematic equations, depending on the moving patterns, to calculate the flight position at every radar acquisition cycle. To obtain higher prediction accuracy, a uniform interpolation method is used to correct the predicted position each second. Finally, a plan trajectory is concatenated by the predicted discrete points. Results of simulations with collected data demonstrate that this approach not only fulfils the goals of traditional methods, such as the prediction of fly-over time and altitude of waypoints along the planned route, but also can be used to plan a complete path for an aircraft with high accuracy. Experiments are conducted to demonstrate the superiority of this approach to some existing methods.

关键词： Velocity vector Hidden Markov model Gaussian mixture model Machine learning Plan path prediction Relative motion between positions(RMBP)

Multiscale modeling of heterogeneous propellants from particle packing tograin failure using a surface-based cohesive approach

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Acta Mechanica Sinica 2012年第3期28卷 746-759页

作者： Shi-Jun Zhi Bing Sun jian-wei zhang School of Astronautics Beihang University100191 BeijingChina

In the present work, a computational frame- work is established for multiscale modeling and analysis of solid propellants. A packing algorithm, considering the am- monium perchlorate （AP） and aluminum （A1） particles as spheres or discs is developed to match the size distribution and volume fraction of solid propellants. A homogenization theory is employed to compute the mean stress and strain of a representative volume element （RVE）. Using the mean results, a suitable size of RVE is decided. Without consider- ing the interfaces between particles and matrix, several nu- merical simulations of the relaxation of propellants are per- formed. The relaxation effect and the nonlinear mechanical behavior of propellants which are dependent on the applied loads are discussed. A new technology named surface-based cohesive behavior is proposed to describe the phenomenon of particle dewetting consisting of two ingredients： a damage initiation criterion and a damage evolution law. Several ex- amples considering contact damage behavior are computed and also nonlinear behavior caused by damaged interfaces is discussed in this paper. Furthermore the effects of the criti- cal contact stress, initial contact stiffness and contact failure distance on the damaged interface model have been studied.

关键词： Solid propellants. Nonlinear mechanical behav-ior- Cohesive. Mesomechanics

A new Bergeria(Flemingitaceae) from the Mississippian of Xinjiang,NW China and its evolutionary implications

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Journal of Palaeogeography 2019年第1期8卷 89-98页

作者： Ru Feng Ashalata D’Rozario jian-wei zhang School of Urban and Environment Science Huaiying Normal University Xinjiang Institute of Ecology and Geography Chinese Academy of Science Department of Botany Narasinha Dutt College

A new Bergeria(Lepidodendrales, Flemingitaceae), B. wenquanensis sp. nov., is described in this paper, typically characterized by the longest and elongated leaf cushions ever found. The specimen, collected from the Mississippian of Wenquan County, Xinjiang Uygur Autonomous Region, China, is represented by a fossil stem about two meters long, with distinct leaf cushions. The genus Bergeria has usually been assigned to partially decorticated Lepidodendron stems. Although Cathaysian Lepidodendron have been extensively reported in China, most of them were found in the central, eastern and southern parts of the country, rarely in northwestern China. This new species is so far the westernmost record and the most isolated representative from the Cathaysian Lepidodendron *** on the distribution of the Cathaysian Lepidodendron during the Mississippian, most of the species were in the South China Plate near the Equator, while the new species is discrete in the north, far from the Equator. According to the spatiotemporal distribution of Cathaysian Lepidodendron, this genus appeared during the Mississippian, a period which was represented by rather few species, it flourished and expanded northwards during the Pennsylvanian, taking the north block of the South China Plate as the center. Since the Cisuralian to the Guadalupian, the genus became gradually sparser in all areas of distribution, probably due to strong climate change. During the Lopingian, the genus migrated southwards to the South China block and had a broader distribution range again, and it became extinct to the end of this interval. The new species is also significant for the evolution of Lepidodendron leaf cushions. During the Mississippian, the primitive species of Lepidodendron usually had narrow, fusiform leaf cushions, while the Pennsylvanian or Permian species were more variable in shape of leaf cushions, from inverted water-drop, rhomboidal, hexagonal, trapeziform to horizontal rhomboidal.

关键词： Cathaysian flora Bergeria Lepidodendron Mississippian Xinjiang

Simulation of the orbit and spin period evolution of the double pulsars PSR J0737-3039 from their birth to coalescence induced by gravitational wave radiation

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Research in Astronomy and Astrophysics 2021年第4期21卷 319-324页

作者： Peng Liu Yi-Yan Yang jian-wei zhang Maria Rah School of Physics and Electronic Engineering Qilu Normal UniversityJinan 250200China School of Physics and Electronic Sciences Guizhou Education UniversityGuiyang 550018China Astronomy Department Beijing Normal UniversityBeijing 100875China Research Institute for Astronomy and Astrophysics of Maragha(RIAAM)-Maragha Iran

The complete orbital and spin period evolutions of the double neutron star(NS)system PSR J0737-3039 are simulated from birth to coalescence,which include the two observed radio pulsars classified as primary NS PSR J0737-3039 A and companion NS PSR J0737-3039 *** employing the characteristic age of PSR J0737-3039 B to constrain the true age of the double pulsar system,the initial orbital period and initial binary separation are obtained as 2.89 h and 1.44 x 106 km,respectively,and the coalescence age or the lifetime from the birth to merger of PSR J0737-3039 is obtained to be 1.38×10^(8)*** the last minute of coalescence,corresponding to the gravitational wave frequency changing from 20 Hz to1180 Hz,we present the binary separation of PSR J0737-3039 to be from 442 km to 30 km,while the spin periods of PSR J0737-3039 A and PSR J0737-3039 B are 27.10 ms and 4.63 s,*** the standard radio pulsar emission model,before the system merged,the primary NS could still be observed by a radio telescope,but the companion NS had crossed the death line in the pulsar magnetic-field versus period(B-P)diagram at which point it is usually considered to cease life as a *** is the first time that the whole life evolutionary simulation of the orbit and spin periods for a double NS system is presented,which provides useful information for observing a primary NS at the coalescence stage.

关键词： PSR J0737–3039 double neutron star pulsar gravitational wave simulation

Critical review in adsorption kinetic models

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第5期10卷 716-724页

作者： Hui QIU Lu LV Bing-cai PAN Qing-jian zhang wei-ming zhang Quan-xing zhang State Key Laboratory of Pollution Control and Resource Reuse Department of Environmental Engineering School of the Environment Nanjing University Nanjing 210093 China

Adsorption is one of the most widely applied techniques for environmental remediation. Its kinetics are of great significance to evaluate the performance of a given adsorbent and gain insight into the underlying mechanisms. There are lots of references available concerning adsorption kinetics, and several mathematic models have been developed to describe adsorption reaction and diffusion processes. However, these models were frequently employed to fit the kinetic data in an unsuitable or improper manner. This is mainly because the boundary conditions of the associated models were, to a considerable extent, ignored for data modeling. Here we reviewed several widely-used adsorption kinetic models and paid more attention to their boundary conditions. We believe that the review is of certain significance and improvement for adsorption kinetic modeling.

关键词： Adsorption kinetics Reaction models Diffusion models Film diffusion Intraparticle diffusion

Application of Fuzzy Logic for Autonomous Bay Parking of Automobiles

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International Journal of Automation and computing 2011年第4期8卷 445-451页

作者： Zhao-jian Wang jian-wei zhang Ying-Ling Huang Hui zhang Aryan Saadat Mehr State Key Laboratory of Automotive Simulation and Control Jilin University Changchun 130025 PRC Changchun Institute of Engineering and Technique Changchun 130117 PRC Department of Mechanical Engineering University of British Columbia Vancouver BC V6T lZ4 Canada Department of Mechanical Engineering University of Victoria PO Box 3055 STN CSC Victoria BC V8W 3P6 Canada Department of Electrical and Computer Engineering University of Saskatchewan 57 Campus Drive Saskatoon SK STN 5A9 Canada

In this paper, we investigate the control problem of autonomous bay parking system. We choose a referenced parking lot and define a suitable parking spot based on some measurements at various places. A kinetic model is set up for the convenience of analysis and simulation. The pose of the car during the parking procedure can be determined by the initial pose, the backward speed, and the steering angle of the wheel. Then, both a fuzzy speed controller and a fuzzy steering controller are designed for the bay parking. Finally, simulation results show the effectiveness of our designed controllers.

关键词： Fuzzy logic bay parking kinetic model simulation autonomous vehicle control.

W-Mo-Si/SiC Oxidation Protective Coating for Carbon/Carbon Composites

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Journal of Materials Science & Technology 2007年第4期23卷 559-562页

作者： Dangshe HOU Kezhi LI Hejun LI Qiangang FU jian wei Yulei zhang National Key Laboratory of Thermostructure Composite Materials Northwestern Polytechnical University Xi＇an 710072 China

A W-Mo-Si/SiC double-layer oxidation protective coating for carbon/carbon （C/C） composites was prepared by a two-step pack cementation technique. XRD （X-ray diffraction） and SEM （scanning electron microscopy）results show that the coating obtained by the first step pack cementation was a thin inner buffer layer of SiC with some cracks and pores, and a new phase of （WxMo1-x）Si2 appeared after the second step pack cementation. Oxidation test shows that, after oxidation in air at 1773 K for 175 h and thermal cycling between 1773 K and room temperature for 18 times, the weight loss of the W-Mo-Si/SiC coated C/C composites was only 2.06%. The oxidation protective failure of the W-Mo-Si/SiC coating was attributed to the formation of some penetrable cracks in the coating.

关键词： C/C composites Coating Microstructure Oxidation

ZnSe/NiO heterostructure-based chemiresistive-type sensors for low-concentration NO_(2) detection

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Rare Metals 2021年第6期40卷 1632-1641页

作者： wei Liu Ding Gu jian-wei zhang Xiao-Gan Li Marina N.Rumyantseva Alexander M.Gaskov School of Microelectronics Key Laboratory of Liaoning for Integrated Circuits TechnologyDalian University of TechnologyDalian 116024China Liaoning Key Laboratory of Integrated Circuit and Biomedical Electronic System Faculty of Electronic Information and Electrical EngineeringDalian University of TechnologyDalian 116024China Laboratory of Chemistry and Physics of Semiconductor and Sensor Materials Chemistry DepartmentMoscow State UniversityMoscow 199991Russia

Novel ZnSe/NiO heterostructure nanocomposites were successfully prepared by one-step hydrothermal *** ZnSe/NiO-based sensor exhibits a response of~96.47% to 8×10^(-6) NO_(2) at 140℃,which is significantly higher than those of intrinsic ZnSe-based(no response)and NiO-based(~19.65%)*** theoretical detection limit(LOD)of the sensor is calculated to be 8.91×10^(-9),indicating that the sensor can be applied to detect the ultralow concentrations of NO_(2).The effect of NiO content on the gas-sensing performance of the nanocomposites was investigated in *** optimal NiO content in the nanocomposite is determined to be15.16%to achieve the highest *** as-fabricated sensor also presents an excellent selectivity to several possible interferents such as methanol,ethanol,acetone,benzene,ammonia and *** enhanced sensing performance can be attributed to the formation of p-p heterostructures between ZnSe and NiO,which induces the charge transfer across the interfaces and yields more active sites.

关键词： ZnSe/NiO heterostructure NO_(2)detection Gas sensors Charge transfer

Constraints on the kinetic energy of type-Ic supernova explosion from young PSR J1906+0746 in a double neutron star candidate

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Chinese Physics B 2021年第6期30卷 721-726页

作者： Yi-Yan Yang Cheng-Min zhang jian-wei zhang De-Hua Wang School of Physics and Electronic Sciences Guizhou Education UniversityGuiyang 550018China CAS Key Laboratory of FAST National Astronomical ObservatoriesChinese Academy of Sciences(CAS)Beijing 100012China Astronomy Department Beijing Normal UniversityBeijing 100875China School of Physics and Electronic Sciences Guizhou Normal UniversityGuiyang 550001China

So far among the nineteen pairs of detected double neutron star(DNS) systems, it is a usual fact that the first-born recycled pulsar is detected, however the youngest DNS system PSR J1906+0746, with the characteristic age of 113 kyr, is one of the three detected DNS as a non-recycled and second-born NS, which is believed to be formed by an electron capture or a low energy ultra-stripped iron core-collapse supernova(SN) explosion. The SN remnant around PSR J1906+0746 is too dim to be observed by optical telescopes, then its x-ray flux limit has been given by Chandra. A reference pulsar PSR J1509-5850 with the young characteristic age of 154 kyr was chosen as an object of comparison, which has an SN remnant observed by Chandra and is believed to be formed by iron core SN explosion. We impose a restriction on the maximum kinetic energy of electron-capture(EC) SN explosion that induces the formation of PSR J1906+0746. The estimated result is(4–8)×10^(50) erg(1 erg= 10-7 J), which is consistent with that of the published simulations of the EC process, i.e., a lower value than that of the conventional iron core SN explosion of(1–2)×10^(51) erg. As suggested, EC process for NS formation is pertained to the subluminous type Ic SN by the helium star with ONeMg core, thus for the first time we derived the kinetic energy of EC SN explosion of DNS, which may be reconciled with the recent observation of type Ic SN 2014 ft with kinetic energy of 2 × 10^(50) erg.

关键词： neutron star pulsar astrophysics high energy astrophysical phenomena