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7th International Conference on simulation and Modeling Methodologies, Technologies and Applications, SIMULTECH 2017

作者： Zhai, Xiang Dai, Feng Qu, Huiyang Zhong, Lingling Du, Chenyong Beijing Complex Product Advanced Manufacturing Engineering Research Center Beijing Simulation Center Beijing China School of Mechanical Engineering Zhejiang University Hangzhou China State Key Laboratory of Intelligent Manufacturing System Technology Beijing Institute of Electronic System Engineering Beijing China Aviation Engineering Institute Civil Aviation Flight University of China Sichuan China Beijing ZhiYuanChuangTong IT Co Ltd Beijing China

ISBN: (纸本)9789897582653

A great amount of existing knowledge is required during the development of aero-craft system. At present, the existing knowledge organization model construct different knowledge model for different stages is difficult to adapt to the complicated product life cycle application. This study proposes a product development oriented knowledge network model focusing on expressing the knowledge demands and connecting the computer-aided system. Under the overall knowledge network model, this study describes the ontology description method of spacecraft product model, development tasks and aerospace terminology. Recommending missile aerodynamic knowledge within the design stage is presented as a case study, and the framework and the method is proved to be effective. © Copyright 2017 by SCITEPRESS - science and technology Publications, Lda. All rights reserved.

关键词： Ontology

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Improving hazard analysis of integrated modular avionics system based on system-theoretic process analysis 17th

Improving hazard analysis of integrated modular avionics sys...

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17th AIAA aviation technology, Integration, and Operations Conference, 2017

作者： Rong, Hao Gu, Qingfan Chen, Zhixiong Xu, Desheng China National Aeronautical Radio Electronics Research Institute Shanghai China Science and Technology on Avionics Integration Laboratory Shanghai China State Key Laboratory for Civil Aircraft Flight Simulation Commercial Aircraft Corporation of China Ltd No.5188 Jin Ke Road Shanghai China Civil Aviation Department No.432 Zi Yue Road Shanghai China

ISBN: (纸本)9781624105081

Integrated modular avionics systems bring new concepts and benefits for function integration and resource utilization in developing advanced aircraft avionics, as well as a series of challenges related to hazard analysis in components interaction and functions operation. When software applications provided independently by the subsystem developers are integrated onto the IMA hardware platform, it is very difficult for designers to understand and predict how the system will behave and what interaction hazards could occur. Although the ARP 4761-based safety analysis methods have solved a large number of safety problems on the development of civil aircraft and system designs in early times, there are some limitations when analyzing more and more complex integrated modular avionics systems in modern times. To gain a good or better understanding and a comprehensive awareness of applications interaction hazards in today’s more complex, software-intensive IMA systems, it is significant to use a method to consider these new causal factors that are not handled by the older techniques and to provide more guidance to the analyst in performing hazard analysis. System-Theoretic Process Analysis (STPA) is one of typical systemic hazard analysis methods. STPA has its foundation in a new accident causality model called STAMP (System-Theoretic Accident Model and Process). STAMP was proposed based on the cybernetics of systems theory. In STAMP, the dysfunctional interactions and requirements flaws during operation are primary types of inadequate control. The STPA-based hazard analysis method is extended in this paper to account for behavior that emerges when software applications are integrated and make functional interaction. This method will be capable of modeling the new causal factors that contribute to component interaction hazards. The paper illustrates the new method with a case that includes real-world avionics display functions, this application of the proposed method will b

关键词： Hazards

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Functionalization of Nylon Fabrics with Dopamine Deposition and TiO2 Nanoparticles Immobilization

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Journal of Donghua University(English Edition) 2017年第1期34卷 82-85页

作者：范佳娜张梅伍静娇邱夷平沈丽刘万双蒋秋冉 College of Textiles Donghua University Shanghai 201620 China Key Laboratory of Textile Science & Technology Ministry of Education Donghua University Shanghai 201620 China Shanghai Key Laboratory of Advanced Micro & Nano Textile Materials Shanghai 201620 China College of Chemistry Chemical Engineering and Biotechnology Donghua University Shanghai 201620 China Collaborative Innovation Center for Civil Aviation Composites Donghua University Shanghai 201620 China

Ultraviolet(UV)radiation can cause degradation or aging of many polymers and shorten the working-life of their ***,UV protective covers are required in various *** with the UV-shielding function possess unique properties compared with those covers in board or film ***_2 nanoparticles(NPs),which were reported to have superior UV blocking function,can be used to produce UV protective covers in combination with ***,efficient and environmentally friendly immobilization of TiO_2 Nps onto the fabrics is ***(PDA),a biomimetic synthetic polymer,has attracted great attentions recently due to its superior affinity to various materials and facile application ***,in this research,the surface of nylon fabrics was modified by PDA to immobilizeTiO_2 *** systematically *** immobilization of the NPs was confirmed by Fourier transform infrared spectrometer(FTIR)and scanning electron microscope(SEM).The functionalized nylon fabrics were proved to exhibit improved UV protection properties even after *** work provides a new and versatile surface modification technique for textiles.

关键词： polydopamine(PDA) nylon fabric TiO2 nanoparticles(NPs) UV protection functionalization

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CHARACTERIZATION, MECHINICAL, THERMAL AND ABLATIVE PROPERTIES OF CERAMIC MODIFIED PHENOLIC RESIN AEROGELS SYNTHSIZED BY AMBIENT PRESSURE DRYING

CHARACTERIZATION, MECHINICAL, THERMAL AND ABLATIVE PROPERTIE...

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第二十一届国际复合材料大会

作者： Jun Zhang Rongying Yin Haiming Cheng Changqing Hong Xinghong Zhang Songhe Meng National Key Laboratory of Science and Technology on Advanced Composites in Special Environments Harbin Institute of Technology China Aerodynamics Research and Development Center Harbin Aircraft industry(Group)Co.Ltd Aviation Industry Corporation of China

During the past few decades, various organic aerogels（AGs） have been synthesized and shown number of exceptional and even unique properties, such as low bulk density, high porosity, grea surface areas, and extremely low thermal conductivity, which enable them being the focus of industr and ***, AGs exhibit substantial performance boosts in numerous applications such a adsorption, separation, catalysis, energy conversion and storage, and so ***, AG generally exhibit high cost, poor thermal and mechanical properties, which seriously restrict the large-scale *** this study, ceramic was introduced into commercial available resin derive aerogel due to the enhancement of silicon to thermal stability and low cost of the *** cerami modified phenolic resin（PR-SiO） aerogel was synthesized by a simple sol-gel polymerization o ceramic precursor, PR, hexamethylenetetramine in an ethylene glycol solution, followed by solven exchange and ambient pressure *** modified effect on the porous structure, textural property and thermal stability was studied by scanning electron microscope（SEM）, nitrogen adsorptio isotherms, and thermogravimetric analysis（TGA）.According to the characterizations of SEM an nitrogen adsorption, the obtained PR-SiO hybrid aerogels have a continuous three dimensiona network that consists of phenolic nano-particles and curved nano-sheets with size from 50 to 90 nm which define numerous mesopores and *** in argon atmosphere indicated that th thermal stability of the PR-SiO aerogels（both maximum decomposition rate and char yield a 1000 ℃） is better than that of the pristine PR *** order to improve the mechanical properties carbon fabric reinforced aerogel composite was prepared by impregnating carbon-bonded carbon fibe（CBCF） composite with the *** the micrographs of the aerogel matrix composite, the aerogel are fully and uniformly occupied the void between carbon fibers, and coated with a t

关键词： Ceramic Phenolic resin Aerogel Mechanical Properties Thermal Properties

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Influence of secondary droplet on separation performance of wave-type vane separator

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IOP Conference Series: Earth and Environmental science 2018年第1期188卷

作者： F L Zhao Q F Liu F Zhang J X Li H L Bo Fundamental Science on Nuclear Safety and Simulation Technology Laboratory Harbin Engineering University Heilongjiang 150001 China Institute of Nuclear and New Energy Technology Tsinghua University Key Laboratory of Advanced Reactor Engineering and Safety of the Ministry of Education Beijing 100084 China

The steam-water separator is a vital device of the steam generator in nuclear power plant. Its separation performance greatly influences the efficiency, safety and reliability of the power station. When the droplet moves in separator, the droplet can collide with the separator wall, and the secondary droplets may generate when the collision velocity of the primary droplet is sufficiently large. To investigate the effect of secondary droplet on separation performance of the separator, the simulation is conducted using droplet motion model and generation model of secondary droplet. The trajectories of both primary droplet and secondary droplet are presented. The effect of the secondary droplet on the separator separation efficiency is analyzed. The results can guide the design of the separator, where both of the droplet motion and the secondary droplets generation need to be considered.

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A step-by-step parameter design method for discrete state space control scheme of dynamic voltage restorer

A step-by-step parameter design method for discrete state sp...

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Annual Conference of Industrial Electronics Society

作者： He Lei Rengcun Fang Dongjun Yang Jingyou Xu Qiushi Xu Zixia Sang Bofeng Gao Yong Kang Lei Wu State Grid Laboratory for Hydro-thermal Power Resources Optimal Allocation & Simulation Technology State Grid HBEPC Economic & Technology Research Institute Wuhan China State Key Laboratory of Advanced Electromagnetic Engineering and Technology Huazhong University of Science and Technology Wuhan China SG Huangshi Electric Power Supply Company Huangshi China

Dynamic Voltage Restorer (DVR), as a device of voltage sag compensation, demands fast transient response, and the disturbance of source voltage is a main impact on control performance. The DVR control strategy based on discrete state space will enhance control bandwidth and stability. However, for the discrete space control system, the number of parameters is relatively more which will lead to a complicated design process. To solve this problem, this paper proposed a control parameter design method based on the idea of virtual resistor. Firstly, by means of state feedback control, an adjustable virtual resistor can be series in filter inductor. According to the requirements of steady-state error, phase margin and Routh's criterion in w domain, the variation regions of PI parameters and virtual resistance can be solved by a step-by-step method, and then the appropriate control parameters can be selected. Experimental results from a digital signal processor-based system are included to support theoretical analysis.

关键词： Resistors Control systems Voltage control Mathematical model Resistance Aerospace electronics Inductors

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Semileptonic B and Bsdecays involving scalar and axial-vector mesons

arXiv

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arXiv 2018年

作者： Kang, Xian-Wei Luo, Tao Zhang, Yi Dai, Ling-Yun Wang, Chao College of Nuclear Science and Technology Beijing Normal University Beijing100875 China Institute of Modern Physics Fudan University Shanghai200443 China School of Physics and Electronics Hunan University Changsha410082 China Institute for Advanced Simulation Institut für Kernphysik Jülich Center for Hadron Physics Forschungszentrum Jülich JülichD-52425 Germany Center for Ecological and Environmental Sciences Key Laboratory for Space Bioscience and Biotechnology Northwestern Polytechnical University Xi'an710072 China

We report our theoretical calculations on the branching fractions for the semileptonic B and Bsdecays based on the form factors in the covariant light-front quark model. That is, B(Bs) → (P, V, S, A)lνl, where P and V denote the pseudoscalar and vector mesons, respectively, while S denotes the scalar meson with mass above 1 GeV and A the axial-vector meson. The branching fractions for the semileptonic B → P and V modes have been measured very well in experiment and our theoretical values are in good agreement with them. The ones for B → S and A modes are our theoretical predictions. There is little experimental information on the semileptonic Bsdecays although much theoretical effort has been done. In addition, we predict the branching fractions of B → D∗0(2400)lνland Bs→ D∗-s0(2317)lνlas (2.31 ± 0.25) × 10-3and (3.07 ± 0.34) × 10-3, in order, assuming them as the conventional mesons with quark-antiquark configuration. The high luminosity e+e--collider SuperKEKB/Belle-II is running, with the data sample enhanced by a factor of 40 compared to Belle, which will provide huge opportunity for the test of the theoretical predictions and further help understand the inner structure of these scalar and axial-vector mesons, e.g., the glueball content of f0(1710) and the mixing angles for the axial-vector mesons. These decay channels can also be accessed by the LHCb experiment. Copyright © 2018, The Authors. All rights reserved.

关键词： Forecasting

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Experimental investigation of flow control using blade end slots in a highly loaded compressor cascade 17

Experimental investigation of flow control using blade end s...

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17th International Symposium on Transport Phenomena and Dynamics of Rotating Machinery, ISROMAC 2017

作者： Tang, Yumeng Liu, Yangwei Lu, Lipeng Lu, Huawei Wang, Ming National Key Laboratory of Science and Technology on Aero-Engine Aero-Thermodynamics School of Energy and Power Engineering Beihang University Beijing100191 China Collaborative Innovation Center of Advanced Aero-Engine Beihang University Beijing100191 China Marine Engineering College Dalian Maritime University Dalian116024 China Shenyang Engine Design and Research Institute Aviation Industry Corporation of China Shenyang110015 China

A detailed experimental investigation is conducted to suppress three-dimensional (3D) corner separation by a proposed passive control method using blade end slots in a highly loaded high-speed compressor cascade. Experiments are carried out under a wide range of incidence angles at Ma=0.59 using blades with and without blade end slots, respectively. Based on the experimental results, extensive comparisons show that the proposed method using blade end slots can efficiently suppress the 3D corner separation and broaden the effective operating range in the highly loaded high-speed compressor cascade. The total pressure loss is significantly reduced under most conditions. The reduction of total pressure loss in the measurement plane is as high as 18.4%, 20.6%, 24.3% and 39.4% at the incidence angle of -1.69, 0, 2 and 4, respectively. Furthermore, spanwise distributions of the pitch-averaged total pressure loss and deviation angle as well as the 3D flow field structures are analyzed to reveal the flow control mechanisms using blade end slots. The blade end slots can generate self-adaptive high momentum jet flow through the pressure difference from blade pressure and suction surface. These jet flows from the blade end slots effect downstream along the blade suction surface and significantly increase the flow momentum in the corner region. The main secondary vortex structures are suppressed by the high momentum jet flow;the 3D corner separation is reduced, and the two-dimesionality in the mid-span region is enhanced. © ISROMAC 2017. All rights reserved.

关键词： Flow control

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Effects of aging temperature on the microstructure and mechanical properties of a Ti2AlNb based alloy

Effects of aging temperature on the microstructure and mecha...

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Chinese Materials Conference on Special and High Performance Structural Materials, CMC 2015

作者： Zhou, Yi Cao, Jingxia Huang, Xu Wang, Bao Mi, Guangbao Beijing Institute of Aeronautical Materials Beijing100095 China Aviation Key Laboratory of Science and Technology on Advanced Titanium Alloys Beijing100095 China

ISBN: (纸本)9783038357612

Effects of aging temperature on microstructure and room temperature mechanical properties of solid solution treated Ti2AlNb based alloy have been investigated. The experimental results showed that after solution treatment and subsequently aging at different temperatures, all the alloys had β/B2, α2 and O three phases, which formed a typical bimodal microstructure with primary α2/O particles and acicular O precipitates dispersing within β/B2 matrix. With increasing the aging temperature, the acicular O precipitates decreased in amount but slightly increased in dimension;the particle α2/O phase did not change in amount but varied in structure, which changed into a core-shell morphology with an α2 core and a rim-O shell, and the rim-O shell was thickened;the change of microstructure led to the decrease in room temperature strength while slight improvement in plasticity. During the tension test, the cracks prefered to propagate along the prior β/B2 grain boundaries which were weaken by the necklace primary α2/O particles. © 2016 Trans Tech Publications, Switzerland.

关键词： Ternary alloys

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Enhanced Strength Through Nanotwinning in the Thermoelectric Semiconductor InSb

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Physical Review Letters 2017年第21期119卷 215503-215503页

作者： Guodong Li Sergey I. Morozov Qingjie Zhang Qi An Pengcheng Zhai G. Jeffrey Snyder State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of Technology Wuhan 430070 China Department of Materials Science and Engineering Northwestern University Evanston Illinois 60208 USA Department of Computer Simulation and Nanotechnology South Ural State University Chelyabinsk 454080 Russia Department of Chemical and Materials Engineering University of Nevada Reno Reno Nevada 89557 USA

The conversion efficiency (zT) of thermoelectric (TE) materials has been enhanced over the last two decades, but their engineering applications are hindered by the poor mechanical properties, especially the low strength at working conditions. Here we used density functional theory (DFT) to show a strength enhancement in the TE semiconductor InSb arising from the twin boundaries (TBs). This strengthening effect leads to an 11% enhancement of the ideal shear strength in flawless crystalline InSb where this theoretical strength is considered as an upper bound on the attainable strength for a realistic material. DFT calculations reveal that the directional covalent bond rearrangements at the TB accommodating the structural mismatch lead to the anisotropic resistance against the deformation combined with the enhanced TB rigidity. This produces a strong stress response in the nanotwinned InSb. This work provides a fundamental insight for understanding the deformation mechanism of nanotwinned TE semiconductors, which is beneficial for developing reliable TE devices.

关键词： Material failure Mechanical deformation Semiconductors Stress Density functional theory

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