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Simulation Assessment of Reliability for k/N Redundancy System Considering Failure Correlativity of Components

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Journal of Donghua University(English Edition) 2015年第6期32卷 979-981页

作者：杜海东曹军海申莹 Department of Technical Support engineering Armored Forces Engineering AcademyPLA

The reliability assessment model of k /N system is built based on Copula function theory considering the failure correlativity existing among components,and then a simulation strategy is presented on the foundation of agent *** components and equipment entity model are designed according to the modeling technique above to describe the operation relationship during the mission phase,and then the simulation system for the assessment of product reliability is *** at last,an example is given with different material support *** research result has shown that the relevance existing in components has effect on the confirmation and optimization of maintenance strategy.

关键词： failure relevance k /N system reliability simulation assessment

Tribological properties and lubricating mechanisms of Cu nanoparticles in lubricant

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中国有色金属学会会刊：英文版 2008年第3期18卷 636-641页

作者：于鹤龙许一史佩京徐滨士王晓丽刘谦 National Key Laboratory for Remanufacturing Academy of Armored Force Engineering

Wear and friction properties of surface modified Cu nanoparticles as 50CC oil additive were studied. The effect of temperature on tribological properties of Cu nanoparticles was investigated on a four-ball tester. The morphologies, typical element distribution and chemical states of the worn surfaces were characterized by SEM, EDS and XPS, respectively. In order to further investigate the tribological mechanism of Cu nanoparticles, a nano-indentation tester was utilized to measure the micro mechanical properties of the worn surface. The results indicate that the higher the oil temperature applied, the better the tribological properties of Cu nanoparticles are. It can be inferred that a thin copper protective film with lower elastic modulus and hardness is formed on the worn surface, which results in the good tribological performances of Cu nanoparticles, especially when the oil temperature is higher.

关键词：铜纳米颗粒摩擦作用润滑机械薄膜温度

J/ψ-N center of mass energy dependence of nuclear absorption effect on J/ψ production

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Chinese Physics C 2010年第1期34卷 22-27页

作者：王宏民侯召宇刘家福孙献静 Physics Department Academy of Armored Forces Engineering of PLA Physics Graduate School Shijiazhuang Railway Institute Institute of High Energy Physics Chinese Academy of Sciences

In this paper, the J/ψ nuclear absorption effect is studied at RHIC and LHC energies with the EKS98 shadowing parameterizations. By assuming that the J/ψ absorption cross section, σ abs , increases with the charmonium-nucleon （J/ψ-N） center of mass energy, s J/ψN , it is found that σ abs should depend on x F （or y） at a certain center of mass energy per nucleon pair,s , especially at LHC energies. The theoretical results with the x F （or y）-dependence of the absorption effect are in good agreement with the experiment data from PHENIX in d-Au collisions and the predicted results will be examined by the forthcoming experimental data from LHC in d-Pb collisions. Finally, we also present baseline calculations of cold nuclear matter effects on J/ψ production in nucleus-nucleus （A-A） collisions and find that the x F （or y）-dependence of absorption effect is very small at both RHIC and LHC energies in A-A collisions.

关键词： x F (or y)-dependence of absorption effect NRQCD model shadowing

Energy dependent growth of nucleon and inclusive charged hadron distributions

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Chinese Physics C 2015年第11期39卷 54-59页

In the Color Glass Condensate formalism, charged hadron p T spectra in p＋p and p＋Pb collisions are studied by considering an energy-dependent broadening of nucleon density distribution. Then, in the glasma flux tube picture, the n-particle multiplicity distributions at different pseudo-rapidity ranges are investigated. Both the theoretical results show good agreement with the recent experimental data from ALICE and CMS at LHC *** predictive results for p T or multiplicity distributions in p＋p and p＋Pb collisions at the Large Hadron Collider are also given in this paper.

关键词： charged hadron PT distributions glasma flux tube gluon saturation model

Surface nanostructure formation mechanism of 45 steel induced by supersonic fine particles pombarding

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Journal of University of Science and Technology Beijing 2008年第5期15卷 561-567页

作者： Dema Ba Shining Ma Changqing Li Fanjun Meng Department of Remanufacture engineering Academy of Armored Force Engineering Beijing 100072 China

By means of supersonic fine particles bombarding （SFPB）,a nanostructured surface layer up to 15 μm was fabricated on a 45 steel plate with ferrite and pearlite phases. To reveal the grain refinement mechanism of SFPB-treated 45 steel,microstructure features of various sections in the treated surface were systematically characterized by X-ray diffraction （XRD）,scanning electron microscopy （SEM） and transmission electron microscopy （TEM）. Grain size increases with an increase of depth from the treated surface. Plastic deformation and grain refinement processes are accompanied by an increase in strain. Plastic deformation in the proeutectoid ferrite phases has precedence over the pearlite phases. Grain refinement in the ferrite phases involves： the onset of dislocation lines （Dls）,dislocation tangles （DTs） and dense dislocation walls （DDWs） in the original grains; the formation of fine lamellar and roughly equiaxed cells separated by DDWs; by dislocation annihilation and rearrangement,the transformation of DDWS into subboundaries and boundaries and the formation of submicron grains or subgrains; the successive subdivision of grains to finer and finer scale,resulting in the formation of highly misoriented nano-grains. By contrast,eutectoid cementite phase accommodated strain in a sequence as follows： onset of elongated,bended and shear deformation under deformation stress of ferrites,short and thin cementites with a width of about 20-50 nm and discontinuous length were formed. Shorter and thinner cementites were developed into ultra-fine pieces under the action of high density dislocation and strains. At the top surface,some cementites were decomposed under severe plastic deformation. Experimental evidences and analysis indicate that surface nanocrystallization of 45 steel results from dislocation activities,high strains and high strain rate are necessary for the formation of nanocrystallites.

关键词： surface nanocrystallization grain refinement mechanism microstructure 45 steel

Charm structure functions and gluon shadowing effects with the AdS/CFT model

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Chinese Physics C 2012年第8期36卷 691-696页

By means of the UGD function extracted from an AdS/CFT inspired saturation model, the charm and bottom structure functions are studied in fixed-order perturbation theory. It is shown that the theoretical results are in good agreement with the recent HERA data. Then, this UGD function is also used to investigate net-kaon rapidity distribution in Au＋Au collisions at RHIC energies and the theoretical results fit well to the BRAHMS data. In the end of this paper, we give the predicted results for nuclear charm structure function at very small x where the popular shadowing parameterizations are invalid.

关键词： AdS/CFT inspired model unintegrated gluon distribution shadowing effect

Health condition monitoring with multiple physical signals in tensile test for double-material friction welding

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Journal of Central South University 2012年第10期19卷 2705-2711页

作者：张玉波徐滨士王海斗杨大祥朱丽娜 State Key Lab for Remanufacturing(academy of armored forces engineering) School of engineering and Technology China University of Geosciences

The manifold physical signals including micro resistance,infrared thermal signal and acoustic emission signal in the tensile test for double-material friction welding normative samples were monitored and collected dynamically by TH2512 micro resistance measuring apparatus,flir infrared thermal camera and acoustic emission equipment which possesses 18 bit PCI-2 data acquisition *** acoustic emission and thermal infrared NDT(non-destructive testing) means were used to verify the feasibility of using resistance method and to monitor dynamic damage of the *** research of the dynamic monitoring system was carried out with multi-information fusion including resistance,infrared and acoustic *** results show that the resistance signal,infrared signal and acoustic emission signal collected synchronously in the injury process of samples have a good ***,thermal and acoustic signals can more accurately capture initiation and development of micro-defects in the *** dynamic micro-resistance method to monitor damage is *** method of multi-information fusion monitoring damage possesses higher reliability,which makes the establishing of health condition diagnosing and early warning platform with multiple physical information monitoring possible.

关键词： micro resistance pictorial infrared photography acoustic emission nondestructive testing dynamic monitoring

Area spectra of BTZ black holes via periodicity

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Science China(Physics,Mechanics & Astronomy) 2013年第9期56卷 1627-1631页

作者： LIU XianMing ZENG XiaoXiong ZHOU ShiWei Department of Physics Hubei University for Nationalities School of Science Chongqing Jiaotong University Department of Foundation Academy of Armored Forces Engineering

Motivated by the recent work that the periodicity of a black hole is responsible for the area spectrum,we exclusively utilize the period of motion of an outgoing wave,which is shown to be related to the vibrational frequency of the perturbed black hole,to study area spectra of a non-rotating BTZ black hole and a rotating BTZ black *** is found that the area spectra and entropy spectra for both space times are equally *** addition,we find that though the entropy spectra of the 3-dimensional BTZ black holes take the same form as those of the 4-dimensional black holes,the area spectra depend on the dimension of space *** result confirms that the entropy spectrum of a black hole is more fundamental than the area spectrum.

关键词： area spectrum periodicity BTZ black holes

Influence of nitrogen implantation into HSS substrate on internal stress and adhesion strength of c-BN films

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中国有色金属学会会刊：英文版 2004年第Z1期14卷 286-290页

作者： ZHANG Ping CAI Zhi-hai TAN Jun XIONG Wan-quan National Key Laboratory for Remanufacturing Academy of Armored Force Engineering Beijing 100072 China National Key Laboratory for Remanufacturing Academy of Armored Force Engineering Beijing 100072 China National Key Laboratory for Remanufacturing Academy of Armored Force Engineering Beijing 100072 China National Key Laboratory for Remanufacturing Academy of Armored Force Engineering Beijing 100072 China

Cubic boron nitride(c-BN) films were deposited on HSS substrate implanted with nitrogen ion by RF-magnetron sputtering. The films were analyzed by bending beam method, scratch test, XRD and AFM. The results show that the implantation of N ion can reduce the internal stress and improve the adhesion strength of the *** critical load comes to 16.92N, compared to 1.75N of c-BN film on the unimplanted HSS. AFM shows that the surface of the c-BN film on the implanted HSS is low in roughness and small in grain size. The phase structure of the nitrogen implanted layer was analyzed by XRD. The influence of nitrogen implanted layer on the internal stress and adhesion strength of c-BN films were also investigated.

关键词： cubic boron nitride film HSS ion implantation internal stress adhesion