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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

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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

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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

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Review of space information technology

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Journal of Systems Engineering and Electronics 2006年第2期17卷 237-244页

作者： Zhong Shan Hou Pingmei The Second academy of china aerospace science & industry corporation Beijing 100854 P. R. China

The features of information technology （IT） are discussed first. On this basis, the features of space information technology （SIT） are presented and SIT is elaborated in five categories. The popularization of SIT is an informatization process and will promote the industrialization of national economy and the modernization of industry such as agriculture. The necessity of the synthetical application of SIT is studied emphatically, and the development trend of SIT is discussed.

关键词： space information technology synthesis miniaturization integration.

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Boost-Phase ballistic missile trajectory estimation with ground based radar

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Journal of Systems Engineering and Electronics 2006年第4期17卷 705-708页

作者： Tang Yuyan Huang Peikang The Second academy of china aerospace science & industry corporation Beijing 100854 P.R.China

A conditional boost-phase trajectory estimation method based on ballistic missile （BM） information database and classification is developed to estimate and predict boos-phase BM trajectory. The main uncertain factors to describe BM dynamics equation are reduced to the control law of trajectory pitch angle in boost-phase. After the BM mass at the beginning of estimation, the BM attack angle and the modification of engine thrust denoting BM acceleration are modeled reasonably, the boost-phase BM trajectory estimation with ground based radar is well realized. The validity of this estimation method is testified by computer simulation with a typical example.

关键词： trajectory estimation boost-phase ground based radar ballistic missile.

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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

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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

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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

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Analysis on damage characteristics and detonation performance of solid rocket engine charge subjected to jet

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Defence Technology（防务技术） 2022年第9期18卷 1552-1562页

作者： Song-lin Pang Xiong Chen Jin-sheng Xu Ge-tu Zhaori Hong-Ying Du School of Mechanical Engineering Nanjing University of Science and TechnologyNanjing210094China The 41st Institute The Sixth AcademyChina Aerospace Science and Industry CorporationHohhot010010China Technology Center Jinxi Industries Group Company LimitedTaiyuan030027China

To further explore the damage characteristics and impact response of the shaped charge to the solid rocket engine(SRE) in storage or transportation, protective armor was designed and the shelled charges model(SCM)/SRE with protective armor impacting by shaped charge tests were conducted. Air overpressures at 5 locations and axial acceleration caused by the explosion were measured, and the experimental results were compared with two air overpressure curves of propellant detonation obtained by related scholars. Afterwards, the finite element software AUTODYN was used to simulate the SCM impacted process and SRE detonation results. The penetration process and the formation cause of damage were analyzed. The detonation performance of TNT, reference propellant, and the propellant used in this experiment was compared. The axial acceleration caused by the explosion was also *** comprehensive comparison, the energy released by the detonation of this propellant is larger, and the HMX or Al particles contained in this propellant are more than the reference propellant, with a TNT equivalent of 1.168-1.196. Finally, advanced protection armor suggestions were proposed based on the theory of woven fabric rubber composite armor(WFRCA).

关键词： Explosion mechanics Shaped charge jet Damage characteristics Detonation performance of propellant

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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

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