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jinfengopteryx Compared to Archaeopteryx,with Comments on the Mosaic Evolution of Long-tailed Avialan Birds

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Acta Geologica Sinica(English Edition) 2007年第3期81卷 337-343页

作者： ji Shu＇an ji qiang Institute of Geology Chinese Academy of Geological Sciences Beijing 100037

jinfengopteryx is a newly uncovered Archaeopteryx-like avialan bird outside Germany, which was found from the Jehol Biota of northern Hebei in northeastern China. It shares many characters only with Archaeopteryx by the possession of three fenestrae in the antorbital cavity, 23 caudal vertebrae and long tail feathers attached to all the caudal vertebrae. But the former differs from the latter in the relatively short and high preorbital region of skull, more and closely packed teeth, much shorter forelimb compared to hindlimb. Such differences indicate jinfengopteryx is even slightly more primitive than Archaeopteryx, although both birds can be placed at the root position of the avialan tree based on cladistic analysis. Shenzhouraptor is suggested to be slightly more advanced than jinfengopteryx ＋ Archaeopteryx, supported by some derived features in teeth, shoulder girdles and forelimbs such as the reduction of tooth number, dorsolaterally directed glenoid facet, very long forelimb and comparatively short manus. Meanwhile, the tail of Shenzhouraptor shows more primitive characters than those of jinfengopteryx and Archaeopteryx, e.g., the strikingly longer tail composed of more caudal vertebrae and the long tail feathers attached only to distal caudal segments. The mixed primitive and advanced characters reveal the evident mosaic evolution among long-tailed avialan birds.

关键词： jinfengopteryx Archaeopteryx long-tailed avialans mosaic evolution Mesozoic

A Kernel PCA Shape Prior and Edge Based MRF Image Segmentation

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Chinese Journal of Electronics 2016年第5期25卷 892-900页

作者： WANG Xili ZHANG Wei ji qiang School of Computer Science Shaanxi Normal University Department of Electrical Computer and Systems Engineering Rensselaer Polytechnic Institute

We introduce both shape prior and edge information to Markov random field(MRF) to segment target of interest in images. Kernel Principal component analysis(PCA) is performed on a set of training shapes to obtain statistical shape representation. Edges are extracted directly from images. Both of them are added to the MRF energy function and the integrated energy function is minimized by graph cuts. An alignment procedure is presented to deal with variations between the target object and shape templates. Edge information makes the influence of inaccurate shape alignment not too severe, and brings result smoother. The experiments indicate that shape and edge play important roles for complete and robust foreground segmentation.

关键词： Kernel Principal component analysis(PCA) Shape prior Edge Markov random field(MRF) Image segmentation

Systematics,Behavior and Living Environment of Shantungosaurus Giganteus(Dinosauria:Hadrosauridae)

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Acta Geologica Sinica(English Edition) 2011年第1期85卷 58-65页

作者： ji Yannan WANG Xuri LIU Yongqing ji qiang School of Earth Sciences and Resources China University ofGeosciences Beijing 100083 China Institute of Geology Chinese Academy of Geological Sciences Beijing 100037 China

On the basis of the taphonomy, osteological anatomy and ontogenetic variation, Zhuchengosaurus maximus Zhao et al., 2007 is considered to be synonymic with Shantungosaurus giganteus Hu, 1973 herein. This paper also deals with the life behavior of S. giganteus and the environment in which S. giganteus lived. S. giganteus is considered to be a terrestrial and gregarious herbivorous dinosaur and lived in hills and intervales in warm weather with plentiful rain and flourishing vegetation.

关键词： Shantungosaurus giganteus life behavior systematics Late Cretaceous Zhucheng Shandong Province

l^(2) Decoupling for Certain Surfaces of Finite Type in R^(3)

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Acta Mathematica Sinica,English Series 2023年第8期39卷 1442-1458页

作者： Zhuo Ran LI ji qiang ZHENG School of Mathematics and Statistics Yancheng Teachers UniversityYancheng 224002P.R.China Institute of Applied Physics and Computational Mathematics P.O.Box 8009Beijing 100088P.R.China

In this article,we establish an 2 decoupling inequality for the surface F_(4)^(2):={(ξ1,ξ2,ξ_(1)^(4)+ξ_(2)^(4)):(ξ1,ξ2)∈[0,1]^(2)}associated with the decomposition adapted to finite type geometry from our previous work[Li,Z.,Miao,C.,Zheng,J.:A restriction estimate for a certain surface of finite type in R^(3).*** ***.,27(4),Paper No.63,24 pp.(2021)].The key ingredients of the proof include the so-called generalized rescaling technique,an l^(2) decoupling inequality for the surfaces{(ξ1,ξ2,φ1(ξ1)+ξ42):(ξ1,ξ2)∈[0,1]^(2)}with φ1 being non-degenerate,reduction of dimension arguments and induction on scales.

关键词： Decoupling inequality finite type reduction of dimension arguments induction on scales

Aerodynamic optimization of a high-lift system with adaptive dropped hinge flap

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Chinese Journal of Aeronautics 2022年第11期35卷 191-208页

作者： qiang ji Yufei ZHANG Haixin CHEN Junke YE School of Aerospace Engineering Tsinghua UniversityBejing 100084China 63870 PLA Troops Huayin 714200China Shanghai Aircraft Design and Research Institute Shanghai 200236China

The Adaptive Dropped Hinge Flap(ADHF) is a novel trailing edge high-lift device characterized by the integration of downward deflection spoiler and simple hinge flap, with excellent aerodynamic and mechanism performance. In this paper, aerodynamic optimization design of an ADHF high-lift system is conducted considering the mechanism performance. Shape and settings of both takeoff and landing configurations are optimized and analyzed, with considering the kinematic constraints of ADHF mechanism, and the desired optimization results were obtained after optimization. Sensitivity analysis proves the robustness of the optimal design. Comparison shows that the ADHF design has better comprehensive performance of both mechanism and aerodynamics than the conventional Fowler flap and simple hinge flap design.

关键词： Adaptive dropped hinge flap Aerodynamic design High-Lift aerodynamics Multidisciplinary optimization Optimization of aircraft design

On the Lower Cretaceous in Yixian County of jinzhou City,Western Liaoning,China

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Acta Geologica Sinica(English Edition) 2011年第2期85卷 437-442页

作者： ji qiang LIU Yongqing jiANG Xiaojun Institute of Geology Chinese Academy of Geological Sciences Beijing 100037 China

Traditionally, the lacustrine deposits in Yixian County of Western Liaoning have been assigned to either ＂the Dakangpu Bed＂ of the Yixian Formation or the jiufotang Formation. However,a 206pb/238U age of 126.47±0.87 Ma is newly obtained from the tuff sample （06051） of the lacustrine deposits in the Baitaigou fossil site of Potaizi village, Yixian County, indicating that the lacustrine deposits in Potaizi area are approximately equivalent to the Wumingshan volcanics of the Sihetun Bed of the Yixian Formation in Beipiao. From our new dating data have arisen some new problems： Where could we find the jiufotang Formation in Yixian County？ How widely distributed is the jiufotang Formation in Western Liaoning？ Could the traditionally named jiufotang Formation somewhere in Western Liaoning be the synchronous deposits of other litho-units （e.g. the Yixian Formation） in different facies？ Could some lacustrine deposits somewhere in Western Liaoning have been assigned to the jiufotang Formation？

关键词： Lower Cretaceous Yixian Formation jiufotang Formation Yixian County

Energy Scattering Theory for Electromagnetic NLS in Dimension Two

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Acta Mathematica Sinica,English Series 2018年第4期34卷 641-654页

作者： Jun Yong ZHANG ji qiang ZHENG Department of Mathematics Beijing Institute of Technology Beijing 100081 P. R. China Beijing Computational Science Research Center Beijing 100193 P. R. China Department of Mathematics Universitd Nice Sophia-Antipolis 06108 Nice Cedex 02 France

We study the well-posedness and long-time behavior of solution to both defocusing and focusing nonlinear Schrodinger equations with scaling critical magnetic potentials in dimension two. In the defocusing case, and under the assumption that the initial data is radial, we prove interaction Morawetz-type inequalities and show the scattering holds in the energy space. The magnetic potential considered here is the Aharonov-Bohm potential which decays likely the Coulomb potential {x}-1.

关键词： Nonlinear Schrodinger equations Aharonov-Bohm potential global well-posedness scat-tering

Flashover in Back-Triggered Photoconductive Semiconductor Switch

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Chinese Physics Letters 2011年第1期28卷 106-108页

作者： SHI Wei jiA ji-qiang ji Wei-Li GUI Huai-Meng Applied Physics Department Xi'an University of Technology Xi'an 710048 State Key Laboratory of Electrical Insulation for Power Equipment Xi'an Jiaotong University Xi'an 710049

Design of a new type of photoconductive semiconductor switches （PCSSs） is presented, and the withstand voltage is improved. The ttashover voltage of the back-triggered PCSS is found to be higher than that of the front-triggered one. By analyzing the differences of the flashover voltage between the back-triggered PCSS and the front-triggered PCSS, a detailed statistics analysis and theoretical explanation are expounded. The experiments also prove that the PCSS we developed could resist a voltage as high as 20 k V under the repetition frequency of 30 Hz.

关键词： Electronics and devices Optics, quantum optics and lasers

Onboard real time modeling of aircraft engines with Hammerstein-Wiener representation

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航空动力学报 2014年第10期29卷 2499-2506页

作者： WANG ji-qiang YE Zhi-feng HU Zhong-zhi jiangsu Province Key Laboratory of Aerospace Power System College of Energy and Power EngineeringNanjing University of Aeronautics and Astronautics

An identification-based approach for aircraft engine modeling using the nonlinear HammersteinWiener representation was ***-Wiener modeling for both limited flight envelope and extended flight envelope was *** shows that the resulting model can be valid over 10%variation of rotational speed of the engine,compared with those linear models that are only valid over 3%—5%change of rotational *** is further demonstrated that the proposed method can be utilized over large envelope up to 20% variation of rotational speed of the *** fundamental idea is to use nonlinear models to extend the feasible/valid region rather than those linear *** may consequently simplify the switching logic in the onboard digital control *** is often overlooked in aircraft engine control community,but has been emphasized in the research.

关键词： aircraft engines engine modeling onboard real time modeling system identification Hammerstein-Wiener representation