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Optoelectronics Letters 2025年第3期 188-192页

作者： YE Zhuang LIU Ruyu SUN Bo School of Information Engineering Chengdu Aviation Vocational and Technical College School of Computer Science and Engineering Hangzhou Normal University Quanzhou institute of Equipment Manufacturing Haixi Institutes Chinese Academy of Sciences

In the field of optoelectronics, certain types of data may be difficult to accurately annotate, such as high-resolution optoelectronic imaging or imaging in certain special spectral ranges. Weakly supervised learning can provide a more reliable approach in these situations. Current popular approaches mainly adopt the classification-based class activation maps (CAM) as initial pseudo labels to solve the task.

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On Behaviors of Functionally Graded SMAs under Thermo-Mechanical Coupling

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Acta Mechanica Solida Sinica 2016年第1期29卷 46-58页

作者： Bingfei Liu Pengcheng Ni Wei Zhang Airport College Civil Aviation University of China Sino-European institute of aviation Engineering Civil Aviation University of China

An analytical solution is obtained for the Functionally Graded Shape Memory Alloy （FG-SMA） composites subjected to thermo-mechanical coupling. Young＇s modulus and thermal expansion coefficient of the material are assumed to vary in different forms of power function through the thickness, with the Poisson＇s ratio being constant. An SMA constitutive model is combined with the averaging techniques of composite to determine the mechanical properties of the FG-SMA composites. Different phase transformation steps and the corresponding stress distributions through the thickness direction are given. The results show that the average stresses decrease as the transformations proceed.

关键词： functionally graded SMAs phase transformation constitutive model

Ignition Process Evolution at High Supersonic Velocities in Channel

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Journal of Thermal Science 2009年第2期18卷 166-172页

作者： M.A.Goldfeldl A.V.Starov K.Yu.Timofeev V.A.Vinogradov institute of Theoretical and Applied Mechanics Central institute of aviation Motors

The results of experimental research of multi-injector combustors in the regime of the attached pipe are *** a source of high-enthalpy working gas (air), hot shot wind tunnel IT-302M of ITAM, the Siberian Branch ofthe Russian Academy of Sciences was used. Tests have been carried out at Mach numbers 3,4 and 5, in a range ofchange of total temperature from 2000K up to 3000K and static pressure from 0.08MPa up to 0.23MPa. Injectorsection has been manufactured in two versions with a various relative height of wedge-shaped injectors with parallelfuel injection. Influence of conditions on the entrance of the combustion chamber on ignition and a stablecombustion of hydrogen was investigated. Intensive combustion of hydrogen has been received only at Machnumbers 3 and 4. Advantage of injector section with the greater relative height of injectors is revealed. Themechanism of fuel ignition in the combustion chamber of the given configuration was investigated: two-step ignitionprocess including 'kindling' and intensive combustion over all channel volume.

关键词： supersonic combustor ignition stable combustion.

A Note on the Auslander-Reiten Conjecture

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Acta Mathematica Sinica,English Series 2013年第10期29卷 1993-1996页

作者： Deng Ming XU Sino-European institute of aviation Engineering Civil Aviation University of China

It is proved that the Auslander-Reiten conjecture is true for local Artin algebras with radical cube zero.

关键词： Local algebras projective modules Auslander-Reiten conjecture

Persymmetric adaptive detection of range-spread targets in subspace interference plus Gaussian clutter

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Science China(Information Sciences) 2023年第5期66卷 271-282页

作者： Tao JIAN Jia HE Yu LIU You HE Congan XU Zikeng XIE Research institute of Information Fusion Naval Aviation University

In this paper, we consider the adaptive detection problem of range-spread targets embedded in subspace interference plus structured Gaussian clutter. The target signal and interference are assumed to lie in two linearly independent subspaces with unknown coordinates. The clutter component is modeled as a complex Gaussian vector with an unknown persymmetric covariance matrix. We leverage the persymmetric structure to design a two-step detector according to the Rao test criterion. The theoretical results show that the proposed detector possesses the constant false alarm rate property with respect to the clutter covariance matrix. Furthermore, the numerical results show that the proposed detector exhibits better detection performance than the existing unstructured subspace detectors, particularly under a limited training data size. In addition, the proposed detector outperforms the existing persymmetric subspace detectors.

关键词： adaptive detection persymmetry structured interference constant false alarm rate Rao test

Tribological performance of organic cadmium compound as lubricant additive

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中国有色金属学会会刊：英文版 2004年第z1期14卷 374-378页

作者： HU Jian-qiang XIE Feng ZHU Huan-qin ZHEN Fa-zheng YAO Jun-bing Department of aviation Oil Air Force Logistics Institute Xuzhou 221000 China Department of Aviation Oil Air Force Logistics Institute Xuzhou 221000 China Department of Aviation Oil Air Force Logistics Institute Xuzhou 221000 China Department of Aviation Oil Air Force Logistics Institute Xuzhou 221000 China First Department Aviation Oil Research Institute Beijing 100000 China

The oil-soluble cadmium dipropyldithiophosphate additive was synthesized. A four-ball tester was used to evaluate the tribological performance of the additive in a mineral oil under different loads and lubricant grease synthesized compared with some commercial additives. The results show that it exhibits excellent antiwear and load-carrying capacities and is better than other additives. The surface analytical tools such as scanning electron microscope (SEM) with energy dispersive X-ray (EDX), X-ray photoelectron spectrometer (XPS) were used to investigate the topography, the compositions, and chemical states of some typical elements on the rubbing surface of worn *** and light topography of worn scar further confirms that the additive shows good antiwear capacities. The results of EDX and XPS analyses indicate that tribochemical mixed protective films consisting of atomic cadmium, sulphides, sulphates and phosphates are formed on the rubbing surface, which contribute to improving the tribological properties of lubricant and grease. Particularly, the soft cadmium film formed plays an important role in improving antiwear properties of oils. Finally, antiwear mechanism of the additive and formation scheme of atomic cadmium was proposed.

关键词： cadmium dipropyldithiophosphate additive extreme pressure antiwear mechanism

Flow Instability of Molten GaAs in the Czochralski Configuration

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Journal of Materials Science & Technology 2007年第3期23卷 395-401页

作者： Shuxian CHEN Mingwei LI institute of Power Engineering Chongqing University Chongqing 400030 China aviation Engineering institute Civil Aviation Flight University of China Guanghan 618307 China

The flow and heat transfer of molten GaAs under the interaction of buoyancy, Marangoni and crystal rotation in the Czochralski configuration are numerically studied by using a time-dependent and three-dimensional turbulent flow model for the first time. The transition from axisymmetric flow to non-axisymmetric flow and then returning to axisymmetric flow again with increasing centrifugal and coriolis forces by increasing the crystal rotation rate was numerically observed. The origin of the transition to non-axisymmetric flow has been proved to be baroclinic instability. Several important characteristics of baroclinic instability in the CZ GaAs melt have been predicted. These characteristics are found to be in agreement with experimental observations.

关键词： Flow transition Baroclinic instability Thermal wave Characteristics GaAs melt

An improved genetic algorithm with dynamic topology

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Chinese Physics B 2016年第12期25卷 583-589页

作者：蔡开泉唐焱武张学军管祥民 School of Electronic and Information Engineering Beihang University Department of General aviation Civil Aviation Management Institute of China

The genetic algorithm （GA） is a nature-inspired evolutionary algorithm to find optima in search space via the interac- tion of individuals. Recently, researchers demonstrated that the interaction topology plays an important role in information exchange among individuals of evolutionary algorithm. In this paper, we investigate the effect of different network topolo- gies adopted to represent the interaction structures. It is found that GA with a high-density topology ends up more likely with an unsatisfactory solution, contrarily, a low-density topology can impede convergence. Consequently, we propose an improved GA with dynamic topology, named DT-GA, in which the topology structure varies dynamically along with the fitness evolution. Several experiments executed with 15 well-known test functions have illustrated that DT-GA outperforms other test GAs for making a balance of convergence speed and optimum quality. Our work may have implications in the combination of complex networks and computational intelligence.

关键词： complex networks genetic algorithm dynamic topology

Effect of P impurity on NiAlΣ5 grain boundary from first-principles study

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Chinese Physics B 2017年第2期26卷 121-126页

作者： Xue-Lan Hu Ruo-Xi Zhao Yang Luo Qing-Gong Song Sino-European institute of aviation Engineering Civil Aviation University of China Tianjin 300300 China College of Science Civil Aviation University of China Tianjin 300300 China

First-principles calculations based on the density functional theory（DFT） and ultra-soft pseudopotential are employed to study the atomic configuration and charge density of impurity P in Ni Al Σ5 grain boundary（GB）. The negative segregation energy of a P atom proves that a P atom can easily segregate in the Ni Al GB. The atomic configuration and formation energy of the P atom in the Ni Al GB demonstrate that the P atom tends to occupy an interstitial site or substitute a Al atom depending on the Ni/Al atoms ratio. The P atom is preferable to staying in the Ni-rich environment in the Ni Al GB forming P–Ni bonds. Both of the charge density and the deformation charge imply that a P atom is more likely to bond with Ni atoms rather than with Al atoms. The density of states further exhibits the interactions between P atom and Ni atom, and the orbital electrons of P, Ni and Al atoms all contribute to P–Ni bonds in the Ni Al GB. It is worth noting that the P–Ni covalent bonds might embrittle the Ni Al GB and weakens the plasticity of the Ni Al intermetallics.

关键词： NiAlΣ5 grain boundary impurity effect first principles

Effects of C impurities on the elastic properties of NiAl intermetallics

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Progress in Natural Science:Materials International 2014年第1期24卷 637-641页

作者： Xuelan Hu Ji Ma Hongwei Dou Yifan Niu Yanfeng Zhang Qinggong Song Sino-European institute of aviation Engineering Civil Aviation University of China College of Science Civil Aviation University of China

The atomic configuration and ductility of Ni Al intermetallics affected by C impurity have been studied with a first-principles pseudo-potential method. The calculation results indicate that for the substitutional cases, C prefers to replace Ni other than Al in most of the cases except for the Ni-rich case. As compared with the interstitial cases, the C atom can be more easily occupy the Ni-rich octahedron position in both of the Ni-rich and Al-rich cases. The brittleness will be decreased and the ductility will be increased after the Ni Al intermetallics doped with the impurity C atom.

关键词： Ni Al intermetallics C impurity Elastic properties First-principles

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