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Bionic Design and Experimental Validation of a Robotic Airship Inspired by the Physalia physalis

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Journal of Bionic Engineering 2024年第2期21卷 740-753页

作者： Yueneng Yang Lili Chen Zhiyang Liu Shifeng Zhang college of Aerospace Science and Engineering National University of Defense TechnologyNo.109Deya RoadKaiFu DistrictChangsha410073China Aerospace Technology Institute China Aerodynamics Research and Development CenterMianyang621000China

The robotic airship is one of the most unique and promising green aircraft,however,as a“lighter-than-air aircraft”and“thermal aircraft”,its long-endurance flight has great difficulties in decreasing drag and controlling buoyancy and pressure under thermal *** this work,we reported a robotic airship inspired by the Physalia physalis,imitating its morphology,physiological structure,and biological *** hull is designed by imitating the morphology of the Physalia physalis,and the gasbags including a helium balloon,two ballonets,and a thermoregulation gasbag are designed by imitating the physiological structure and biological behaviors of the pneumatophore,bladder,and gland of the Physalia physalis,*** results show that the bionic airship has an increase of about 40%in lift-to-drag and decreases the pressure in helium balloon by 47.5%under thermal effects,and has better aerodynamic performances and thermoregulation performances than conventional airships.

关键词： Robotic airship Bionic design Aerodynamic performances Thermoregulation Physalia physalis

Theoretical Study of Compressibility and Thermoelasticity of LaNi5-xAlx （x= 0.3, 0.5 and 1.0）

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Chinese Physics Letters 2008年第12期25卷 4352-4355页

作者：陈东肖启敏赵英路熊宝库余本海施德恒 college of Physics and Electronic Engineering Xinyang Normal University Xinyang 464000 Department of Foundation The First Aeronautical College of Air Force Xinyang 464000 college of Physics and Electronic Engineering Ludong University Yantai 264025

The compressibility, the temperature dependence of bulk modulus, the pressure dependence of normalized volume V/V0, thermal expansion coefficient and Debye temperature of LaNi5-xAlx compounds are successfully obtained using the first-principles plane-wave pseudopotential （PW-PP） method, the EOSFIT6.0 software and the quasiharmonic Debye model. The rapid decrease of relative lattice constant a/a0 shows that the deformation is easier in directions normal to the c-axis than that along it. The relationships between bulk modulus B and pressure at different temperatures are also analysed. It is found that the bulk modulus B increases monotonically with increasing pressure. Moreover, the pressure dependences of thermal expansion and Debye temperature are also successfully obtained. The calculated results are in agreement with the experimental data.

关键词： field emission molybdenum dioxide enhancement factor

First-Principles Calculations of Elastic Properties of Cubic Ni2MnGa

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Chinese Physics Letters 2009年第1期26卷 205-208页

作者：陈东肖启敏赵英路余本海王春雷施德恒 college of Physics and Electronic Engineering Xinyang Normal University Xinyang 464000 Department of Foundation The First Aeronautical College of Air Force Xinyang 464000 college of Physics and Electronic Engineering Ludong University Yantai 264025

Dependence of bulk modulus on both pressure and temperature, the elastic constants Cij and the pressure and temperature dependence of normalized volume V/Vo of cubic Ni2MnGa alloy are successfully obtained using the first-principles plane-wave pseudopotential （PW-PP） method as well as the quasi-harmonic Debye model. We analyse the relationship between bulk modulus and temperature up to 800 K and obtain the relationships between bulk modulus B and pressures at different temperatures. It is found that the bulk modulus B increases monotonically with increasing pressure. Moreover, the temperature dependences of the Debye temperature are also analysed. The calculated results are in agreement with the available experimental data and the previous theoreticM results.

关键词： STRUCTURAL-PROPERTIES PHASE-TRANSFORMATION ALLOYS SOLIDS ORDER MGF2

A bottom-up method for module-based product platform development through mapping,clustering and matching analysis

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Journal of Central South University 2016年第3期23卷 623-635页

作者：张萌李国喜曹建平龚京忠吴宝中 college of Mechatronic Engineering and Automation National University of Defense TechnologyChangsha 410073China Naval aeronautical and Astronautical Institute Qingdao 266041China

Designing product platform could be an effective and efficient solution for manufacturing firms. Product platforms enable firms to provide increased product variety for the marketplace with as little variety between products as possible. Developed consumer products and modules within a firm can further be investigated to find out the possibility of product platform creation. A bottom-up method is proposed for module-based product platform through mapping, clustering and matching analysis. The framework and the parametric model of the method are presented, which consist of three steps:(1) mapping parameters from existing product families to functional modules,(2) clustering the modules within existing module families based on their parameters so as to generate module clusters, and selecting the satisfactory module clusters based on commonality, and(3) matching the parameters of the module clusters to the functional modules in order to capture platform elements. In addition, the parameter matching criterion and mismatching treatment are put forward to ensure the effectiveness of the platform process, while standardization and serialization of the platform element are presented. A design case of the belt conveyor is studied to demonstrate the feasibility of the proposed method.

关键词： product platform development bottom-up method mapping clustering matching

Stability and performance analysis of a jump linear control system subject to digital upsets

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Chinese Physics B 2015年第4期24卷 6-15页

作者：王蕊孙辉马振洋 Tianjin Key Laboratory for Civil Aircraft Airworthiness and Maintenance Civil Aviation University of China college of aeronautical Automation Civil Aviation University of China

This paper focuses on the methodology analysis for the stability and the corresponding tracking performance of a closed-loop digital jump linear control system with a stochastic switching signal. The method is applied to a flight control system. A distributed recoverable platform is implemented on the flight control system and subject to independent digital upsets. The upset processes are used to stimulate electromagnetic environments. Specifically, the paper presents the scenarios that the upset process is directly injected into the distributed flight control system, which is modeled by independent Markov upset processes and independent and identically distributed （IID） processes. A theoretical performance analysis and simulation modelling are both presented in detail for a more complete independent digital upset injection. The specific examples are proposed to verify the methodology of tracking performance analysis. The general analyses for different configurations are also proposed. Comparisons among different configurations are conducted to demonstrate the availability and the characteristics of the design.

关键词： stochastic process stability and performance analysis jump linear system digital upsets

Analysis of the Microstructure and Permeability of the Laminates with Different Fiber Volume Fraction

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Journal of Donghua University(English Edition) 2008年第3期25卷 282-285页

作者：马悦李炜梁子青 college of Textiles Donghua University National Key Lab of Advanced Composites Institute of Aeronautical Materials

Microstructures of laminates produced by epoxy/carbon fibers with different fiber volume fraction were studied by analyzing the composite *** main result of the compaction of reinforcement is the flatting of bundle shape,the reducing of gap and the embedment of bundles among each *** void content outside the bundle decreased sharply during the compaction until it is less than that inside the bundle when the fiber volume fraction is over 60%.The resin flow velocity in the fiber tow is 102-104 times greater than the flow velocity out the fiber tow no matter the capillary pressure is taken into account or not.

关键词： microstructure fiber zolume fraction permeability capillary pressure wid

CONSOLIDATION BEHAVIOR OF MECHANICALLY ALLOYED γ-TiAl

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Acta Metallurgica Sinica(English Letters) 1995年第Z1期8卷 569-576页

作者： LI Chenggong YANG Wanhong LUO Zhiping(Institute of aeronautical Materials, Beijing 100095, China FROES F H, FREFER A) Institute of Materials and Advanced Processing, college of Mines, University of Idaho,Moscow. ID83843-3026. USA Inst of aeronautical Materials Beijing China

Use of mechanically alloying for preparation of Ti-35at.%Al results in significant reduction in crystal size, so the ductility of alloy can be improved Consolidation of Mechanically alloyed γ -TiAl is difficult because of its poor workability. The present paper will discuss recent studies on consolidation behavior by using different methods, such as explosive compaction, hot isostatic pressing, and rapid omnidirectional compaction, etc.. The microstructure and property of the samples are evaluated.

关键词： mechanical alloying explosive compaction hot isostatic pressing rapid omnidirectional compaction

Study on the Mechanical Properties of Ni-Ti-Cu Shape Memory Alloy Considering Different Cu Contents

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Computer Modeling in Engineering & Sciences 2022年第6期131卷 1601-1613页

作者： Bingfei Liu Yangjie Hao Transportation Science and Engineering college Civil Aviation University of ChinaTianjin300300China aeronautical Engineering college Civil Aviation University of ChinaTianjin300300China

By adding copper to increase the performance,the Ni-Ti-Cu Shape Memory Alloy(SMA),has been widely used in the field of engineering in recent years.A thermodynamic constitutive model for Ni-Ti-Cu SMA considering different copper contents is established in this *** results for two different copper contents,as examples,are compared with the experimental results to verify the accuracy of the theoretical *** on the verified constitutive model,the effects of different copper content on the mechanical properties of Ni-Ti-Cu SMA and the tensile and compressive asymmetric properties of Ni-Ti-Cu SMA are finally discussed,respectively.

关键词： Shape memory alloy copper contents constitutive model tension and compression asymmetric

MODIFIED H-R MIXED VARIATIONAL PRINCIPLE FOR MAGNETOELECTROELASTIC BODIES AND STATE-VECTOR EQUATION

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Applied Mathematics and Mechanics(English Edition) 2005年第6期26卷 722-728页

作者：卿光辉邱家俊刘艳红 aeronautical Mechanics & Avionics Engineering college Civil Aviation University of China Department of Mechanics and Engineering Measurement School of Mechanical Engineering

Based upon the Hellinger-Reissner (H-R) mixed variational principle for three-dimensional elastic bodies, the modified H-R mixed variational theorem for magnetoelectroelastic bodies was established. The state-vector equation of magnetoelectroelastic plates was derived from the proposed theorem by performing the variational operations. To lay a theoretical basis of the semi-analytical solution applied with the magnetoelectroelastic plates, the state-vector equation for the discrete element in plane was proposed through the use of the proposed principle. Finally, it is pointed out that the modified H-R mixed variational principle for pure elastic, single piezoelectric or single piezomagnetic bodies are the special cases of the present variational theorem.

关键词： magnetoelectroelastic body variational principle laminated plates state-vector equation semi-analytical solution