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Defence Technology（防务技术） 2023年第7期25卷 231-248页

作者： Hao wu Peng-fei wu Zhang-song Shi Shi-yan Sun Zhong-hong wu School of Ordnance Engineering Naval University of EngineeringWuhan430033China

In the internet of battlefield things, ammunition is becoming networked and intelligent, which depends on location information. Therefore, this paper focuses on the self-organized network collaborative localization of munitions with an aerial three-dimensional(3D) highly-dynamic topographic structure under a satellite denied environment. As for aerial networked munitions, the measurement of munitions is objectively incomplete due to the degenerated and interrupted link of munitions. For this reason, a cluster-oriented collaborative localization method is put forward in this paper. Multidimensional scaling(MDS) was first integrated with a trilateration localization method(TLM) to construct a relative localization algorithm for determining the relative location of a mobile cluster network. The information related to relative velocity was then combined into a collaborative localization framework to devise a TLM-vMDS algorithm. Finally, an iterative refinement algorithm based on scaling by majorizing a complicated function(SMACOF) was employed to effectively eliminate the influence of incomplete link observation on localization accuracy. Compared with the currently available advanced algorithms, the proposed TLM-vMDS algorithm achieves higher localization accuracy and faster convergence for a cluster of extensively networked munitions, and also offers better numerical stability and robustness for highspeed motion models.

关键词： Highly-dynamic topographic structure MDS Relative ranging Aerial ammunition ad hoc network

Programmed cell death involved in the schizolysigenous formation of the secretory cavity in Citrus sinensis L. (Osbeck)

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Chinese Science Bulletin 2010年第20期55卷 2160-2168页

作者： CHEN Ying wu hong Research Center for Medicinal Plants College of Life Sciences South China Agricultural University Guangzhou 510642 China

The developmental types of secretory cavities in Citrus remain unclear and whether or not programmed cell death is involved in the developmental process of secretory cavities remains an *** cavity formation in Citrus sinensis fruits,this work uncovered novel evidence to delineate secretory cavity formation in schizolysigeny,supporting the possibility of utilizing secretory cavities as a new cell biology model for investigating the molecular mechanism of plant programmed cell death.

关键词：程序性细胞死亡分泌腔脐橙分子生物学机制 s形发育类型分泌物柑桔

Experimental Investigation on the Vapor Chambers with Sintered Copper Powder Wick

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Journal of Thermal Science 2021年第6期30卷 1938-1950页

作者： HUANG Dou JIA Li wu hong AAKER Olav Beijing Key Laboratory of Flow and Heat Transfer of Phase Changing in Micro and Small Scale School of MechanicalElectronic and Control EngineeringBeijing Jiaotong UniversityBeijing 100044China Faculty of Engineering 0stfold University CollegeBox700N-1757Norway

High power electronics units generate high-density heat flux,which poses a significant threat to the reliability of these *** vapor chamber(VC)has a very high heat transfer rate and has a wide range of applications in the heat dissipation of electronic *** with sintered copper powder wicks sized as irregular shape copper powder 50μm(I-50μm),I-75μm,I-110μm,I-150μm were studied in this *** effect of liquid filling ratio was *** results indicated that the thermal resistance of all VCs decreased with the increase of heating *** capillary performance of wick was the dominant factor for the heat transfer performance of VCs with different kinds of wick.A capillary performance factor was proposed to evaluate the capillary performance of *** capillary performance factor of VC with the wick of I-75μm was much higher than that of the other types of VC in this *** heat source surface temperature of VCs could be affected by filling ratio and wick ***,it should be insensitive to the filling ratio when a better capillary performance factor was *** the same heating area and similar structure,the maximum heat flux density of the VC would decrease as the height of vapor cavity decreased.

关键词： vapor chamber copper powder capillary performance heat transfer performance thermal resistance

Delay-dependent Wide-area Damping Controller Synthesis Approach Using Jensen’s Inequality and Evolution Algorithm

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CSEE Journal of Power and Energy Systems 2023年第5期9卷 1774-1785页

作者： Wencheng wu Xiaoru Wang hong Rao Baorong Zhou the School of Electrical Engineering Southwest Jiaotong UniversityChengduSichuan Province 610021China the Southwest Electric Power Design Institute Sichuan Province 610056China the State Key Laboratory of HVDC Electric Power Research InstituteCSGGuangzhou 510663China

A time-delay-dependent wide-area damping controller synthesis approach,based on Jensen’s integral inequality and evolution algorithm,is developed to suppress the adverse effect of time delay on the supplemental control of high-voltage direct current(DC)transmission ***,the state-space model of hybrid AC/DC systems with time delay is derived and the delay-dependent criteria for the stability of the closed-loop system are provided based on Jensen’s integral ***,initial solutions are randomly generated to overcome the difficulty of solving the nonlinear matrix ***,the time-delay stability upper bound of the controller is optimized using the differential evolution *** comparison to popular time-delay stable controller design methods,such as the free-weighting-matrix approach,the proposed method based on output feedback realization requires fewer decision variables and is more suitable for large-scale hybrid AC/DC *** examples are introduced to verify the effectiveness of the proposed method.

关键词： Damping suppression delay-dependent control differential evolution algorithm Jensen’s inequality output feedback time-varying delay wide-area control

Influence of delta phase precipitation on static recrystallization of cold-rolled Inconel 718 alloy in solid solution treatment

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Journal of Iron and Steel Research International 2019年第2期26卷 148-153页

作者： Neng-yong Ye Ming Cheng Shl-hong Zhang hong-wu Song hong-wei Zhou Institute of Metal Research Chinese Academy of SciencesShenyang 110016LiaoningChina School of Mechanical Engineering Taizhou UniversityTaizhou 318013ZhejiangChina State Key Laboratory of Advanced Processing and Recycling of Non-ferrous Metals Lanzhou University of TechnologyLanzhou 730050GansuChina

Due to the improvement in fatigue strength of cold-rolled blades,the static recrystallization behavior of cold-rolled Inconel 718 alloy in the solid solution treatment was investigated with the methods of optical microscopy and electron backscattered *** effect ofδphase precipitation on the static recrystallization process was also *** results show thatδphase preferentially precipitates comparing to static *** by theδphase preferential precipitation process,sub-grain migration is the main nucleation mechanism in the static recrystallization of coldrolled Inconel 718 alloy at 980°***,strain-induced boundary migration also exists as an aided nucleation mechanism when the rolling reduction is less than 30%.

关键词： Cold rolling Inconel 718 alloy Static recrystallization δphase precipitation

GNSS Spoofing Detection Based on Consistency Check of Velocities

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Chinese Journal of Electronics 2019年第2期28卷 437-444页

作者： TAO Huiqi wu Hailing LI hong LU Mingquan Department of Electronic Engineering Tsinghua University China Satellite Navigation Project Center

Spoofing attacks for Global navigation satellite system(GNSS) would cause the abnormal changes of receiver measurements. Monitoring the abnormal changes is the main pattern of anti-spoofing *** of Doppler shifts are important for GNSS spoofing detection. Most researchers focus on the consistency of Doppler such as the consistency of carrier Doppler and code rate. But the method is powerless in some *** shift measurement is proportional to change rate of pseudorange, and the relationship would be broken in the case of spoofing attack. As both Doppler measurements and pseudoranges are related to velocity of receiver,two approaches of computing velocity can be used to check the consistency of Doppler shifts and pseudoranges measurements. An efficient spoofing detection method based on the consistency check of velocities is proposed in the paper. Principle of the method is given in detail and its performance evaluations are provided as well. Simulation results demonstrate the effectiveness of the solution.

关键词： GNSS Anti-spoofing Pseudoranges Doppler Velocity Consistency

On hp refinements of independent cover numerical manifold method——some strategies and observations

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Science China(Technological Sciences) 2023年第5期66卷 1335-1351页

作者： ZHANG Ning ZHENG hong LI Xu wu WenAn School of Civil Engineering Qinghai UniversityQinghai810016China Key Laboratory of Urban Security and Disaster Engineering Ministry of EducationBeijing University of TechnologyBeijing100081China Key Laboratory of Urban Underground Engineering of Ministry of Education Beijing Jiaotong UniversityBeijing100091China

In this paper,strategies are provided for a powerful numerical manifold method(NMM)with h and p refinement in analyses of elasticity and *** new NMM is based on the concept of the independent cover,which gets rid of NMM's important defect of rank deficiency when using higher-order local approximation *** techniques are *** terms of mesh generation,a relationship between the quadtree structure and the mathematical mesh is established to allow a robust *** to the condition number,a scaling based on the physical patch is much better than the classical scaling based on the mathematical patch;an overlapping width of 1%–10%can ensure a good condition number for 2nd,3rd,and 4th order local approximation functions;the small element issue can be overcome after the local approximation on small patch is replaced by that on a regular *** numerical accuracy,local approximation using complete polynomials is necessary for the optimal convergence *** issues that may damage the convergence rate should be *** first is to approximate the curved boundary of a higher-order element by overly few straight lines,and the second is excessive overlapping ***,several refinement strategies are verified by numerical examples.

关键词： independent cover numerical manifold method hp refinement partition of unity higher order element condition number

Beyond pixels:Learning from multimodal hyperspectral superpixels for land cover classification

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Science China(Technological Sciences) 2022年第4期65卷 802-808页

作者： hong DanFeng wu Xin YAO Jing ZHU XiaoXiang Key Laboratory of Computational Optical Imaging Technology Aerospace Information Research InstituteChinese Academy of SciencesBeijing 100094China School of Computer Science(National Pilot Software Engineering School) Beijing University of Posts and TelecommunicationsBeijing 100876China Remote Sensing Technology Institute German Aerospace Center(DLR)Wessling 82234Germany Data Science in Earth Observation Technical University of MunichMunich 80333Germany

Despite tons of advanced classification models that have recently been developed for the land cover mapping task,the monotonicity of a single remote sensing data source,such as only using hyperspectral data or multispectral data,hinders the classification accuracy from being further improved and tends to meet the performance *** this reason,we develop a novel superpixel-based subspace learning model,called Supace,by jointly learning multimodal feature representations from HS and MS superpixels for more accurate LCC *** can learn a common subspace across multimodal RS data,where the diverse and complementary information from different modalities can be better combined,being capable of enhancing the discriminative ability of to-be-learned features in a more effective *** better capture semantic information of objects in the feature learning process,superpixels that beyond pixels are regarded as the study object in our Supace for *** experiments have been conducted on two popular hyperspectral and multispectral datasets,demonstrating the superiority of the proposed Supace in the land cover classification task compared with several well-known baselines related to multimodal remote sensing image feature learning.

关键词： classification hyperspectral image land cover multimodal multispectral image remote sensing subspace learning superpixels

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New Start-up Method for a Closed-Cycle Compression System with Gas Bearings and Its Characteristics

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Chinese Journal of Mechanical Engineering 2020年第6期33卷 118-133页

作者： Huaqi Lian hong wu Yulong Li Chengjun Rong National Key Laboratory of Science and Technology on Aero Engines Aero-thermodynamics&Collaborative Innovation Center for Advanced Aero-Engine School of Energy and Power EngineeringBeihang UniversityBeijing100191China

Gas bearings,which have the advantages of low frictional resistance and power loss,high rotational speed and high temperature operation,and long life,are more suitable than are traditional liquid lubricated bearings because of their high precision,high rotational speed,and special condition ***,the problem of starting a closed-cycle compression system with gas bearings still needs to be solved for practical ***,a new start-up method for a closed-cycle compression system with aerostatic gas bearings is proposed in this ***,this paper presents a numerical simulation and experimental investigation of the method’s feasibility and characteristics during the start-up process when the gas tank’s initial pressure is *** results show that the gas tank volume is approximately directly proportional to the start-up time allowable,and a gas tank volume sufficiently small,which not only ensures the feasibility of start-up,but also affects other components only slightly,can be obtained.A perfect combination of radial and axial loads also can be achieved to make the start-up time allowable as long as possible.R134a is a better choice for the working medium than is air,as the start-up time allowable is longer,which leads to a smaller gas *** research proposes a new start-up method for a closed-cycle compression system with aerostatic gas bearings which has sufficient load capacity to support system during the start-up method.

关键词： Gas bearing Start-up method Gas tank Start-up time allowable

Fabrication of Carbon Nanotubes and Rare Earth Pr Reinforced AZ91 Composites by Powder Metallurgy

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Chinese Journal of Mechanical Engineering 2021年第2期34卷 213-222页

作者： Ning Li hong Yan Qingjie wu Zeyu Cao School of Mechanical Electrical Engineering Nanchang UniversityNanchang 330031China School of Aviation Manufacturing Engineering Nanchang Hangkong UniversityNanchang 330069China

It can be known from a large number of research results that improving the dispersibility of CNTs can effectively optimize the mechanical properties of the corresponding metal matrix ***,the crucial issue of increasing the bonding of CNTs and the matrix is still *** this paper,a novel method was developed to increase interfacial bonding strength by coating titanium oxide(TiO2)on the surface of *** rare earth Pr and TiO2@CNTs-reinforced AZ91matrix composites were successfully fabricated by powder *** press sintering and hot extrusion of the milled powder was *** hot extrusion,the influence of TiO2@CNTs on the microstruc-ture and mechanical properties of the composites were *** results showed that the coating process can improve the distribution of CNTs in Mg *** CNTs refined the grains of the matrix,and the CNTs were presented throughout the extrusion *** the TiO2@CNTs content was 1.0 wt.%,the yield strength(YS),ultimate ten-sile strength(UTS),and elongation of the alloy attained maximum *** values were improved by 23.5%,82.1%,and 40.0%,respectively,when compared with the AZ91 *** interfacial bonding was achieved,which resulted in an effective tensile loading transfer at the *** carried the tensile stress and were observed on the tensile fracture.

关键词： Carbon nanotubes Titanium oxide AZ91 Coating Rare earth