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Chinese Journal of Polymer science 2017年第4期35卷 480-489页

作者： Qian Du Jing Shao Yao Gao Wei-li Li Hong-kun Tian Dong-hang Yan 耿延候 Fo-song Wang School of Material science and Engineering and Collaborative Innovation Centre of Chemical science and Engineering(Tianjin) Tianjin University the 46th institute of the sixth academy of china aerospace science&industry corporation State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of Sciences

three acceptor-donor-acceptor （A-D-A） conjugated oligomers, i.e., O1, 02 and 03, have been synthesized using diketopyrrolopyrrole （DPP） as an electron-acceptor unit, and naphtho[1,2-b：5,6-b＇]dithiophene （NDT）, anthra[1,2-b：5,6- b＇]dithiophene （ADT） or dithieno[3,2-b：Y,2＇-b＇]naphtbo[1,2-b：5,6-b＇]dithiophene （DTNDT） as electron-donor unit. these oligomers exhibit identical highest occupied molecular orbital （HOMO） and lowest unoccupied molecular orbital （LUMO） energy levels, which were ca. -5.1 and -3.3 eV, respectively. Upon thermal annealing, all three oligomers formed thin films with ordered microstructures, and their organic thin film transistors （OTFTs） exhibited p-type transport behavior. the mobility was increased with an extension of the size of D-units. 03 showed the best OTFT performance with the mobility of up to 0.20 cm2·V-1 ·s-1. the film quality of 03 was improved by adding 1 wt% poly（methylmethacrylate）（PMMA）. In consequence, the mobility of the O3-based devices was further enhanced to 0.30 cm2·V-1 ·s-1.

关键词： Diketopyrrolopyrrole (DPP) thienoacene Conjugated oligomers Organic thin-film transistors (OTFTs)

Novel High-nitrogen Energetic Compound Based on Semicarbazide-substituted Tetrazine

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Chemical Research in Chinese Universities 2012年第6期28卷 931-935页

作者： ZHANG Jlan-guo LIANG Yan-hui XIE Shao-hua FENG Jin-ling WANG Kun ZHANG Tong-lai State Key Laboratory of Explosion science and Technology Beij'ing Institute of Technology Beo'ing 100081 P. R. China the 46th institute of the sixth academy of china aerospace science & industry corporation Hohhot 010010 P. R. China

A novel energetic compound 3-（3,5-dimethylpyrazol-1-yl）-6-semicarbazide-1,2,4,5-tetrazine（DSTZ） was prepared and characterized by elemental analysis and Fourier transform infrared（FTIR） *** crystal structure was determined by X-ray single crystal diffraction *** crystal belongs to the monoclinic system with a P2 1 /c space group,a=0.9942（7） nm,b=0.5067（3） nm,c=1.1830（8） nm,β=109.616°,Z=2 and D c =1.475 g/cm *** extensive hydrogen bonds,the molecules were linked together to form a three-dimensional herringbone-like *** analysis of the compound was carried out via differential scanning calorimetry（DSC） and thermogravimetric-derivative thermogravimetry（TG-DTG）.Under a nitrogen atmosphere at a heating rate of 10 K/min,DSTZ decomposed directly in a range of 493―513 *** one intense exothermic process was observed and the decomposition products were all gaseous *** sensitivity properties were determined,showing that the title complex was insensitive to friction,impact and flame.

关键词： 1 2 4 5-Tetrazine Semicarbazide Crystal structure Sensitivity property

Discrete decision model and multi-agent simulation of the Liang Zong two-chain hierarchical organization in a complex project

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Journal of Systems Engineering and Electronics 2018年第2期29卷 311-320页

作者： MAI Qiang ZHAO Yueqiang AN Shi School of Management Harbin Institute of Technology Defense Technology academy China Aerospace Science & Industry Corporation

Different from the organization structure of complex projects in Western countries, the Liang Zong hierarchical organization structure of complex projects in china has two different chains, the chief-engineer chain and the general-director chain,to handle the trade-off between technical and management decisions. However, previous works on organization search have mainly focused on the single-chain hierarchical organization in which all decisions are regarded as homogeneous. the heterogeneity and the interdependency between technical decisions and management decisions have been neglected. A two-chain hierarchical organization structure mapped from a real complex project is constructed. then, a discrete decision model for a Liang Zong two-chain hierarchical organization in an NK model framework is proposed. this model proves that this kind of organization structure can reduce the search space by a large amount and that the search process should reach a final stable state more quickly. For a more complicated decision mechanism, a multi-agent simulation based on the above NK model is used to explore the effect of the two-chain organization structure on the speed, stability, and performance of the search process. the results provide three insights into how, compared with the single-chain hierarchical organization, the two-chain organization can improve the search process: it can reduce the number of iterations efficiently; the search is more stable because the search space is a smoother hill-like fitness landscape; in general, the search performance can be ***, when the organization structure is very complicated, the performance of a two-chain organization is inferior to that of a single-chain organization. these findings about the efficiency of the unique Chinese-style organization structure can be used to guide organization design for complex projects.

关键词： complex project two-chain hierarchical organization discrete decision model multi-agent simulation

Analysis of single frequency modulation for passive hydrogen maser

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Journal of Systems Engineering and Electronics 2017年第4期28卷 661-668页

作者： Hefei Zheng Jing Li Wenming Wang Lianshan Gao Keming Feng Beijing institute of Radio Metrology and Measurement The Second Academy of China Aerospace Science and Industry CorporationBeijing 100854 China

Based on the theory of the passive hydrogen maser, along with the technology of frequency modulation and modulation transfer spectroscopy, the theoretical expression of the single frequency modulation for the passive hydrogen maser and the function of the cavity and H line error signals separation are derived, which are basically coincident with the experiment. the absorption and dispersion spectrum curves with different resonance widths show that the cavity and hydrogen transition serve as discriminators, and the two error signals can be separated. through the calculations of the two error signals in the passive hydrogen maser, it analyzes the traditional method of the two error signals separation, and then describes a new improved method for the passive hydrogen servo loops consisting in the use of a single modulation frequency and frequency discrimination. A null interaction of the two error signals for the new selection of the phase setting is deduced theoretically and validated by the simulation. the preliminary experimental result confirms the feasibility of this new approach, which can reduce the influence from the cavity frequency variety on the crystal oscillator and contribute significantly to the long term performance of the passive hydrogen maser.

关键词： passive hydrogen maser single frequency modulation frequency discrimination

Technology and test results of space adaptability of passive hydrogen maser

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Journal of Systems Engineering and Electronics 2017年第2期28卷 251-256页

作者： Hefei Zheng Lianshan Gao Keming Feng Jing Li Wenming Wang Chunyan Cao Jihong Zhang Beijing institute of Radio Metrology and Measurement Beijing 100854 China the Second academy of china aerospace science and industry corporation Beijing 100854 China

Based on the operating principle and the electric property design of the passive hydrogen maser, the technology and test results of its space adaptability are carried out under the special launch conditions and space environment. the various perturbations affecting the output frequency of such a standard used for the navigation satellite system are specified, such as magnetic field change, vibration, thermal vacuum and radiation. through the adaptability technology in the aspects above, the security and reliability of the space passive hydrogen maser sufficiently fulfill the requirements of space operation. At present, the space passive hydrogen maser is working normally on board, indicating that the space adaptability satisfies the design requirement.

关键词： passive hydrogen maser space adaptability performance test

Bi-material Topology Optimization Using Analysis Mesh-Independent Point-Wise Density Interpolation

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Acta Mechanica Solida Sinica 2019年第6期32卷 698-712页

作者： Xiaoyu Suo Zhan Kang Xiaopeng Zhang Yaguang Wang State Key Laboratory of Structural Analysis for Industrial Equipment Dalian University of TechnologyDalian 116024China the 41st institute of the sixth academy of china aerospace science&industry corporation Hohhot 010010China

this paper extends the independent point-wise density interpolation to the bimaterial to pology optimization to improve the structural static or dynamic proper *** contras t to the conventional elemental density-based topology optimization approaches,this method employs an analysis-mesh-separated material density field discretization model to describe the topology evolution of bi-material structures within the design *** be specific,the density design variable points can be freely positioned,independently of the field points used for discretization of the displacement *** this means,a material interface description of relatively high quality can be achieved,even when unstructured finite element meshes and irregular-shaped elements are used in discretization of the analysis *** examples,regarding the minimum static compliance design and the maximum fundamental eigen-frequency design,are presented to demonstrate the validity and applicability of the proposed formulation and numerical *** is shown that this method is free of numerical difficulties such as checkerboard patterns and the“islanding”phenomenon.

关键词： Topology optimization Bi-material Independent point-wise density interpolation Topology description Material interface Dynamic topology optimization

Extension of e^N method to general three-dimensional boundary layers

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Applied Mathematics and Mechanics(English Edition) 2017年第7期38卷 1007-1018页

作者： Lei ZHAO Gaotong YU Jisheng LUO Department of Mechanics Tianjin University the 41st institute of No.6 academy China Aerospace Science & Industry Corporation

In order to extend the eN method to general three-dimensional boundary layers, the conservation law of the imaginary parts for the wave parameters with a fixed wave vector is deduced. the compatibility relationship （CR） and the general theory of ray tracing （RT）, which have been extensively used in conservative systems, are applied to a general three-dimensional boundary layer belonging to non-conservative systems. Two kinds of eN methods, i.e., the eN-CR method and the eN-RT method, are established. Both the two kinds of methods can wavenumber and the amplitude of the be used to predict the evolutions of the spanwise disturbances in general three-dimensional boundary layers. the reliability of the proposed methods is verified and validated by performing a direct numerical simulation （DNS） in a hypersonic general three-dimensional boundary layer over an aircraft model. the results are also compared with those obtained by other eN methods, indicating that the proposed methods have great potential applications in improving the transition prediction accuracy in general three-dimensional boundary layers.

关键词： eN method ray tracing theory transition prediction three-dimensionalboundary layer

Tracking algorithm of BPSK signal in low bit SNR and high dynamic scenarios

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Journal of Beijing institute of Technology 2015年第1期24卷 118-127页

作者：王鹏陈国瑛 Beijing institute of Electronic System Engineering the Second academy of china aerospace science and industry corporation

A new tracking algorithm is proposed aiming at the tracking problem in low bit signal-to- noise ratio （i. e. , Eb/N0 ） scenarios, in which the bit clock regenerated by bit synchronization loop decides loop update moment. the double frequency processing and non-coherent accumulation tech- nologies are applied to eliminate the impact of data polarity inversion, and then long time accumula- tion improves the input signal-to-noise ratio of discriminator. the frequency locked loop and phase locked loop constitute a carrier loop in parallel, which can meet the high dynamic demands. the ef- fectiveness of this algorithm has been corroborated by theoretical analysis, simulation and measure- ments, and the new tracking algorithm has been used in an aerospace engineering project successfully.

关键词： tracking double frequency processing non-coherent low bit signal-to-noise ratio

Target tracking in infrared imagery using a novel particle filter

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Chinese Optics Letters 2009年第7期7卷 576-579页

作者：王芳林刘尔琦杨杰郁生阳周越 institute of Image Processing and Pattern Recognition Shanghai Jiao Tong University institute of the Second academy China Aerospace Science and Industry Corporation

To address two challenging problems in infrared target tracking, target appearance changes and unpre- dictable abrupt motions, a novel particle filtering based tracking algorithm is introduced. In this method, a novel saliency model is proposed to distinguish the salient target from background, and the eigenspace model is invoked to adapt target appearance changes. To account for the abrupt motions efficiently, a two- step sampling method is proposed to combine the two observation models. the proposed tracking method is demonstrated through two real infrared image sequences, which include the changes of luminance and size, and the drastic abrupt motions of the target.

关键词： Infrared imaging Nonlinear filtering Targets

Parametric modeling of hypersonic ballistic data based on time varying auto-regressive model

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science china(Technological sciences) 2020年第8期63卷 1396-1405页

作者： HU YuDong LI JunLong ZHANG Zhao JING WuXing GAO ChangSheng Department of aerospace Engineering Harbin Institute of TechnologyHarbin 150001China china aerospace science and industry corporation Beijing 100854China

For describing target motion in hypersonic vehicle defense,a parametric analyzing and modeling method on ballistic data is proposed based on time varying auto-regressive *** data are regarded as non-stationary random signal,where the hidden internal law is ***,ballistic data are decomposed into smooth linear trend signal and non-stationary periodic skip signal with ensemble empirical mode decomposition method to avoid mutual interference between different modal ***,the linear trend signal and the periodic skip signal are modeled *** linear trend signal is approximated by power function regressive estimator and the periodic skip signal is modeled based on time varying auto-regressive *** order to determine optimal model orders,a novel method is presented based on information theoretic criteria and the criteria of minimizing the mean absolute ***,the consistency test is conducted by investigating the time-frequency spectrum characteristics and statistical properties of outputs of the parametric model established above and dynamics model under the same initial *** results demonstrate that the parametric model established by the proposed method shares a high consistency with the original dynamics model.

关键词： hypersonic vehicle parametric modeling ballistic data decomposition time varying auto-regressive periods drift