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Novel approach to GPS/SINS integration for IMU alignment

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Journal of Systems Engineering and Electronics 2011年第3期22卷 513-518页

作者： wei sun Feng sun School of Geomatics Liaoning Technical UniversityFuxin 123000P.R.China College of Automation Harbin Engineering UniversityHarbin 150001P.R.China

Strapdown inertial navigation system（SINS） requires an initialization process that establishes the relationship between the body frame and the local geographic *** process,called alignment,is generally used to estimate the initial attitude *** is possible because an accurate determination of the inertial measurement unit（IMU） motion is available based on the measurement obtained from global position system（GPS）.But the update frequency of GPS is much lower than *** to the non-synchronous data streams from GPS and SINS,the initial attitude angles may not be computed accurately *** addition,the estimated initial attitude angles may have relatively large uncertainties that can affect the accuracy of other navigation *** paper presents an effective approach of matching the velocities which are provided by GPS and *** this approach,a digital high-pass filter,which implements a pre-filtering scheme of the measured signal,is used to filter the Schuler cycle of discrete velocity difference between the SINS and *** results show that this approach improves the accuracy greatly and makes the convergence time satisfy the required accuracy.

关键词： strapdown inertial navigation system(SINS) global position system(GPS) integration alignment high-pass filter.

Applications of thermostatically controlled loads for demand response with the proliferation of variable renewable energy

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Frontiers in Energy 2022年第1期16卷 64-73页

作者： Meng SONG wei sun Jiangsu Provincial Key Laboratory of Smart Grid Technology and Equipment Southeast UniversityNanjing 210096China Department of Electrical and Computer Engineering University of Central FloridaOrlandoFL 32816USA

More flexibility is desirable with the proliferation of variable renewable resources for balancing supply and demand in power *** controlled loads(TCLs)attract tremendous attentions because of their specific thermal inertia capability in demand response(DR)*** effectively manage numerous and distributed TCLs,intermediate coordinators,e.g.,aggregators,as a bridge between end users and dispatch operators are required to model and control TCLs for serving the ***,intermediate coordinators get the access to fundamental models and response modes of TCLs,make control strategies,and distribute control signals to TCLs according the requirements of dispatch *** the other hand,intermediate coordinators also provide dispatch models that characterize the external characteristics of TCLs to dispatch operators for scheduling different *** this paper,the bottom-up key technologies of TCLs in DR programs based on the current research have been reviewed and compared,including fundamental models,response modes,control strategies,dispatch models and dispatch strategies of TCLs,as well as challenges and opportunities in future work.

关键词： thermostatically controlled load demand response renewable energy power system operation

Universal sums of three quadratic polynomials

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Science China Mathematics 2020年第3期63卷 501-520页

作者： Zhi-wei sun Department of Mathematics Nanjing University

Let a,b,c,d,e and f be integers with a≥ c≥ e> 0,b>-a and b≡a(mod 2),d>-c and d≡c(mod 2),f>-e and f≡e(mod 2).Suppose that b≥d if a=c,and d≥f if c=*** b(a-b),d(c-d) and f(e-f) are not all zero,we prove that if each n∈N={0,1,2,...} can be written as x(ax+b)/2+y(cy+d)/2+z(ez+f)/2 with x,y,z∈N then the tuple(a,b,c,d,e,f) must be on our list of 473 candidates,and show that 56 of them meet our *** b∈[0,a),d∈[0,c) and f∈[0,e),we investigate the universal tuples(a,b,c,d,e,f) over Z for which any n∈N can be written as x(ax+b)/2+y(cy+d)/2+z(ez+f)/2 with x,y,z∈Z,and show that there are totally 12,082 such candidates some of which are proved to be universal tuples over *** example,we show that any n∈N can be written as x(x+1)/2+y(3y+1)/2+z(5z+1)/2 with x,y,z∈Z,and conjecture that each n∈N can be written as x(x+1)/2+y(3y+1)/2+z(5z+1)/2 with x,y,z∈N.

关键词： representations of integers universal sums quadratic polynomials

Weak convergence of Dirichlet processes

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Science China Mathematics 1998年第1期41卷 8-21页

作者： sun wei Probabilty Laboratory Institute of Aplied Mahematics Chinese Academy of Sciences Bejing 100080China

Weak convergence of Markov processes is studied by means of Dirichlet forms and two theorems for weak convergence of Hunt processes on general metric spaces are *** applications,examples for weak convergence of symmet... 详细信息

关键词： strictly quasi-regular Dirichlet form weak convergence Mosco convergence s.{A^(n)}-nest

Numerical investigation of transcritical liquid film cooling in a methane/oxygen rocket engine

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航空动力学报 2011年第4期26卷 903-916页

作者： YANG wei sun Bing School of Astronautics Beijing University of Aeronautics and Astronautic Beijing 100191 China

Transcritical film cooling was investigated by numerical study in a methane cooled methane/oxygen rocket *** respective time-averaged Navier-Stokes equations have been solved for the compressible steady three-dimensional(3-D) *** flow field computations were performed using the semi-implicit method for pressure linked equation(SIMPLE) algorithm on several blocks of nonuniform collocated *** calculation was conducted over a pressure range of 202 650.0 Pa to 1.2×107 Pa and a temperature range of 120.0 K to 3 568.0 ***-nine different cases were simulated to calculate the impact of different *** results show that mass flow rate,length,diameter,number and diffused or convergence of film jet channel,injection angle and jet array arrangements have great impact on transcritical film cooling ***,shape of the jet holes and jet and crossflow turbulence also affect the wall temperature *** rows of film arranged in different axial angles and staggered arrangement were proposed as new liquid film *** radial angles have impact on the film cooling effectiveness in two row-jets cooled *** case of in-line and staggered arrangement are almost the same in the region before the second row of jets,but a staggered arrangement has a higher film cooling effectiveness from the second row of jets.

关键词： liquid film cooling numerical study rocket transcritical semi-implicit method for pressure linked equation(SIMPLE) film cooling effectiveness

Adaptive Maneuvering Frequency Method of Current Statistical Model

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IEEE/CAA Journal of Automatica Sinica 2017年第1期4卷 154-160页

作者： wei sun Yongjian Yang Department of Applied Science Xijing University Aeronautics and Astronautics Engineering College Air Force Engineering University

Current statistical model(CSM) has a good performance in maneuvering target tracking. However, the fixed maneuvering frequency will deteriorate the tracking results, such as a serious dynamic delay, a slowly converging speedy and a limited precision when using Kalman filter(KF) algorithm. In this study, a new current statistical model and a new Kalman filter are proposed to improve the performance of maneuvering target tracking. The new model which employs innovation dominated subjection function to adaptively adjust maneuvering frequency has a better performance in step maneuvering target tracking, while a fluctuant phenomenon appears. As far as this problem is concerned, a new adaptive fading Kalman filter is proposed as well. In the new Kalman filter, the prediction values are amended in time by setting judgment and amendment rules,so that tracking precision and fluctuant phenomenon of the new current statistical model are improved. The results of simulation indicate the effectiveness of the new algorithm and the practical guiding significance.

关键词： Current statistical model(CSM) maneuvering target tracking adaptive fading Kalman filter(AFKF)

Modeling and Finite-Time Tracking Control for Mobile Manipulators with Affine and Holonomic Constraints

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Journal of Systems Science & Complexity 2016年第3期29卷 589-601页

作者： sun wei WU Yuqiang School of Mathematics Science Liaocheng University Institute of Automation Qufu Normal University

This paper focuses on the problem of modeling and finite-time tracking control for mobile manipulators with affine and holonomic constraints. A reduced dynamic model is obtained by appropriately processing anne and holonomic constraints, respectively. Then finite-time tracking controllers are designed to ensure that output tracking errors of closed-loop system converge to zero in finite time while the constraint force remains bounded. Finally, detailed simulation results are provided to confirm the effectiveness of the control strategy.

关键词： Affine constraints finite-time tracking holonomic constraints mobile manipulators

Mechanical properties and failure behavior of 3D printed thermoplastic composites using continuous basalt fiber under high-volume fraction

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Defence Technology（防务技术） 2023年第9期27卷 237-250页

作者： Hang Zhang wei-fu sun State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing100081China Beijing Institute of Technology Chongqing Innovation Center Chongqing401120China Explosion Protection and Emergency Disposal Technology Engineering Research Center of the Ministry of Education Beijing10081China

Continuous basalt fiber(CBF)is an outstanding inorganic fiber produced from nature,which has a wide range of applications in the field of armor protection of national defense ***,the mechanical response and failure mechanism of 3D printed CBF reinforced components are still not well ***,the 3D printing thermoplastic composites with high volume fraction CBF have been successfully prepared by fused deposition modelling(FDM)*** effects of fiber printing direction and polymer matrix type on the tensile and flexural properties of the 3D printed composites have been explored,and the detailed failure morphology has been characterized using scanning electron microscopy and optical *** was found that under high fiber volume fraction,3D printed CBF reinforced polyamides(PA)composites have the best ability to maintain material integrity of the composites,followed by acrylonitrile butadiene styrene(ABS)and high impact polystyrene(HIPS).Besides,the results from rule of mixtures can accurately predict the longitudinal Young’s modulus of the 3D printed specimens,but there exists a large discrepancy for the prediction of the tensile *** microstructure analysis shows that the failure modes of 3D printed composites mainly include fiber debonding,fiber pull-out,stress whitening and matrix cracking.

关键词： Additive manufacturing Continuous basalt fiber Failure behavior Mechanical properties Thermoplastic composites

Information Flow Scheduling in Concurrent Multi-Product Development Based on DSM

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Chinese Journal of Mechanical Engineering 2017年第5期30卷 1101-1111页

作者： Qing-Chao sun wei-Qiang Huang Ying-Jie Jiang wei sun School of Mechanical Engineering Dalian University of Technology

Multi-product collaborative development is adopted widely in manufacturing enterprise, while the present multi-project planning models don＇t take techni- cal/data interactions of multiple products into account. To decrease the influence of technical/data interactions on project progresses, the information flow scheduling models based on the extended DSM is presented. Firstly, infor- mation dependencies are divided into four types： series, parallel, coupling and similar. Secondly, different types of dependencies are expressed as DSM units, and the exten- ded DSM model is brought forward, described as a block matrix. Furthermore, the information flow scheduling methods is proposed, which involves four types of opera- tions, where partitioning and clustering algorithm are modified from DSM for ensuring progress of high-priority project, merging and converting is the specific computation of the extended DSM. Finally, the information flow scheduling of two machine tools development is analyzed with example, and different project priorities correspond to different task sequences and total coordination cost. The proposed methodology provides a detailed instruction for information flow scheduling in multi-product development, with specially concerning technical/data interactions.

关键词： Concurrent multi-product development Information flow planning Extended DSM Projectpriority