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Dynamic assessment method of air target threat based on improved GIFSS

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Journal of Systems Engineering and Electronics 2019年第3期30卷 525-534页

作者： FENG Jinfu ZHANG Qiang hu junhua LIU An Aeronautics Engineering College Air Force Engineering University

As the air combat environment becomes more complicated and changeable, accurate threat assessment of air target has a significant impact on air defense operations. This paper proposes an improved generalized intuitionistic fuzzy soft set (GIFSS) method for dynamic assessment of air target threat. Firstly, the threat assessment index is reasonably determined by analyzing the typical characteristics of air targets. Secondly, after the GIFSS at different time is obtained, the index weight is determined by the intuitionistic fuzzy set entropy and the relative entropy theory. Then, the inverse Poisson distribution method is used to determine the weight of time series, and then the time-weighted GIFSS is obtained. Finally, threat assessment of five air targets is carried out by using the improved GIFSS (I-GIFSS) and comparison methods. The validity and superiority of the proposed method are verified by calculation and comparison.

关键词： threat dynamic assessment generalized intuitionistic fuzzy soft set (GIFSS) intuitionistic fuzzy entropy relative entropy inverse Poisson distribution method

Study on the Coincident-Loop Transient Electromagnetic Method in Seafloor Exploration——Taking Jiaodong Polymetallic Mine as a Model

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Journal of Earth Science 2021年第1期32卷 25-41页

作者： Yixing Ma junhua hu Yanjun Chang Zujian Liu Development and Research Center of China Geological Survey Beijing 100037China Technical Guidance Center for Mineral Resources of Ministry of Natural Resources Beijing 100083China State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin China Institute of Water Resources and Hydropower ResearchBeijing 100038China Department of Structures and Materials China Institute of Water Resources and Hydropower ResearchBeijing 100038China Institute of Geophysics and Geometrics China University of GeosciencesWuhan 430074China China Aero Geophysical Survey and Remote Sensing Center for Natural and Resources Beijing 100083China

The transient electromagnetic(TEM)method becomes more urgent than ever for marine ex-ploration due to abundant resource reserves and the increasing undersea engineering construction activities,especially in the offshore exploration of mineral deposits such as Sanshandao gold ***,the re-search and application of TEM method in marine environment are still challenged by many *** contradiction motivates our study on the coincident-loop TEM in seafloor *** TEM response of coincident loops is firstly derived in the integral form,based on the potential functions in Helmholtz equ-ations for a magnetic source locating in the whole-space layered *** frequency-domain vertical magnetic field is described as the Hankel integral with double first-order Bessel functions of first ***-condly,the time-domain induced voltage is obtained by transforming the frequency-domain response through the cosine transform and then taking the derivative of *** simultaneously solve the Hankel transform and the cosine transform,a novel algorithm is introduced by adapting the fixed-point quadra-ture and extrapolation via the Shanks ***,a typical conductivity model for marine po-lymetallic deposit is designed to investigate the characteristic of TEM response under various *** results demonstrate that existence of conductive seawater causes the TEM response to increase significantly and decay *** air-sea reflected electromagnetic waves lead to a significantly large fake negative response(NR)in shallower seawater with depth less than 300 *** in the height of loops will weaken and delay the anomaly response and shorten the observation *** height of configu-ration should be no more than 100 m for shallower targets and 50 m for deeper targets,*** observation time-window should cover 10-1000 *** in the radius of loops only enhances the TEM response proportionally but hardly improve

关键词： marine transient electromagnetic method coincident loops induced polarization air-wave effects

Bird diversity and the conservation value of a new Ramsar site:Guangdong Haifeng Wetlands, China

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Integrative Zoology 2011年第3期6卷 266-278页

作者： junhua hu Zhigang JIANG Chunlan ZHANG Feng XIAO huijian hu Chengdu Institute of Biology Chinese Academy of SciencesChengduChina Institute of Zoology Chinese Academy of SciencesBeijingChina South China Institute of Endangered Animals GuangzhouChina

Wetlands are critical habitats for ***,wetlands are being degraded at an accelerating rate due to global human activity,and a disproportionate fraction of wetland-dependent bird species are in *** evaluated the conservation value of a new Ramsar site,Guangdong Haifeng Wetlands,China,for birds,by comparing bird communities(using line transect data)in 3 different districts:Gongping,Dongguan Lian’anwei and *** recorded 139 species of birds,including 26 species that are protected at a national *** had the highest species richness and diversity,whereas Dongguan Lian’anwei had the highest abundance of birds and the lowest species ***,Gongping had both the lowest species richness and the lowest *** ende-mism of constituent species differed among districts,and the bird communities were *** were significant seasonal differences in the species richness and the number of *** had the highest species richness and *** present study identifies the high conservation value of Haifeng Wetlands for both waterbirds and terrestrial *** findings suggest that conservation efforts in Haifeng Wetlands and other wetlands should focus not only on wintering migratory birds,but also on resident *** accomplish effective conservation,we should consider the reserve and surrounding wetlands as a whole,incorporating ecological research,education and local economic development.

关键词： assemblage conservation Important Birds Area seasonal variation

Research on consensus of multi-agent systems with and without input saturation constraints

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Journal of Systems Engineering and Electronics 2021年第4期32卷 947-955页

作者： QI Duo hu junhua LIANG Xiaolong ZHANG Jiaqiang ZHANG Zhihao Air Traffic Control and Navigation College Air Force Engineering UniversityXi’an 710051China Shaanxi Province Lab.of Meta-Synthesis for Electronic&Information System Xi’an 710051China Aeronautical Engineering College Air Force Engineering UniversityXi’an 710038China

In recent years,with the continuous development of multi-agent technology represented by unmanned aerial vehicle(UAV)swarm,consensus control has become a hot spot in academic *** this paper,we put forward a discrete-time consensus protocol and obtain the necessary and sufficient conditions for the second-order consensus of the second-order multi-agent system with a fixed structure under the condition of no saturation *** theoretical derivation verifies that the two eigenvalues of the Laplacian of the communication network matrix and the sampling period have an important effect on achieving *** we construct and verify sufficient conditions to achieve consensus under the condition of input saturation *** results show that consensus can be achieved if velocity,position gain,and sampling period satisfy a set of inequalities related to the eigenvalues of the Laplacian ***,the accuracy and validity of the theoretical results are proved by numerical simulations.

关键词： multi-agent system consensus control input constraint distributed control

Self-consistent assessment of Li^(+) ion cathodes:Theory ***

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Journal of Energy Chemistry 2021年第8期30卷 229-241,I0006页

作者： Hongjie Xu Weidong Xiao Zhuo Wang junhua hu Guosheng Shao School of Materials Science and Engineering Zhengzhou UniversityZhengzhou 450001China Centre for International Cooperation on Designer Low-carbon&Environmental Materials(CDLCEM) Zhengzhou UniversityZhengzhou 450001China Zhengzhou Materials Genome Institute(ZMGI) Zhengzhou 450100China

Transition metal oxide cathodes such as layered Li Co O_(2),spinel Li Mn_(2)O_(4) and olivine Li Fe PO4 have been commercialized for several decades and widely used in the rechargeable Li-ion batteries(LIBs).While great theoretical efforts have been made using the density functional theory(DFT)method,leading to insightful understanding covering materials stability and functional properties,the lack of consistency in choices of functionals and/or convergence criteria makes it somewhat difficult to compare *** is therefore highly useful to assess these established systems towards self-consistency,thus offering a reliable working basis for theoretical formulation of novel *** in this work,we have carried out systematic DFT calculations on the basis of recently established framework covering both thermodynamic stability,functional properties and associated *** have been made in selfconsistent selection of exchange-correlation(XC)functionals in terms of dependable accuracy with affordable computational cost,which is essential for high-throughput first-principles *** outcome of the current work on three established cathode systems is in very good agreement with experimental data,and the methodology is to provide a solid basis for designing novel cathode materials without using costing non-local exchange-correlation functionals for structure-energy calculations.

关键词： Li-ion batteries Intercalation-type oxide cathodes Ab initio approaches Self-consistency Density functional theory

Durable self-polishing antifouling Cu-Ti coating by a micron-scale Cu/Ti laminated microstructure design

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Journal of Materials Science & Technology 2021年第20期79卷 62-74页

作者： Jiajia Tian Kangwei Xu junhua hu Shijie Zhang Guoqin Cao Guosheng Shao State Centre for International Cooperation on Designer Low-Carbon and Environmental Material(SCICDLCEM) School of Materials Science and EngineeringZhengzhou UniversityZhengzhou450001China Special Functional Materials Department Luoyang Ship Material Research InstituteLuoyang471023China School of Life Science Zhengzhou UniversityZhengzhou450001China

Marine biofouling is a major issue deteriorating the service performance and lifespan of marine *** development of a durable,long-term,and environment-friendly antifouling coating is therefore of significant importance but still a critical challenge in maritime ***,we developed a Cu-Ti composite antifouling coating with micron-sized alternating laminated-structure of Cu/Ti by plasma spraying of mechanically mixed Cu/Ti *** coating was designed to enable controlled release of Cu ions through galvanic dissolution of Cu laminates from the Cu/Ti micro-galvanic cell in aqueous *** showed that remarkable antifouling efficiency against bacterial survival and adhesion up to~100%was achieved for the Cu-Ti ***/Ti micro-galvanic cell was in-situ formed within Cu-Ti coating and responsible for its Cu ions *** successive dissolution of Cu laminates resulted in the formation of micro-channels under Ti laminates near surface,which contributed to controlled slow Cu ions release and self-polishing ***,environment-friendly antifouling capability and∼200%longer antifouling lifetime than that of the conventional organic antifouling coatings can be achieved for the Cu-Ti *** the other hand,as compared to the conventional organic antifouling coatings,the Cu-Ti composite coating presented much higher mechanical durability due to its strong adhesion strength,excellent mechanical properties,and two orders lower wear *** present laminated Cu-Ti coating exhibits combination of outstanding antifouling performance and high mechanical durability,which makes this coating very potentially candidates in marine antifouling application.

关键词： Marine antifouling Cu-Ti coating Plasma spraying Micro-galvanic dissolution Durable Self-polishing

Trophic Niche Shifts in Mountain Feirana Frogs under human-mediated Habitat Transformations

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Asian Herpetological Research 2021年第2期12卷 234-241页

作者： Shengnan YANG Chunlan ZHANG Wenbo LIAO Na LI junhua hu Chengdu Institute of Biolog y Chinese Academy of SciencesChengdu 610041SichuanChina Guangdong Key Laborator y of Animal Conservation arnd Rescurce Urilization Guangdong Public Labnoratory of Wild Animnal Conservatimand UilizationInstitute of Zoolog yGuangdong Academy of SciencesGuangzhou 510260GuangdongChina Key Laboratory of Southwest China Wilife Resources Conservation(Ministry of Education) China West Normal UniversityNanchong 6370OOSichuanChina CAS Key Liberatory of Mountain Ecological Restoration and Bioresource Utilization e Ecological Restoration and Biodiversity Conservation Key Liberatory of Sichuan Province Chengdu Institute of BiologyChinese Academy of SciencesChengdu 610041SichuanChina

Urbanization can induce environmental changes, disturbing habitat transformation process, and resulting in niche shift of species and local extinctions. Amphibians have experienced worldwide population declines, with ha bitat loss acting as one of the most disruptive causes. How amphibian species response to changing habitats could be reflected in their utilization and assimilation of resources. Using stable isotopes, we explored trophic niche variation between natural and transformed habitats for three closely related frog species in the genus Feirana(F. quadranus, F. taihangnica and F. kangxianensis). Our results indicated that the δ~(13)C value was negatively correlated with body size(snout-vent length) and the δ~(15)N value increased along with the ontogenetic process. The δ~(13)C values were significantly different among habitat types, and the variation of δ~(15)N values was relatively limited in different disturbed gradients. Urban groups displayed broader trophic niche width than both rural and natural groups. When species in sympatry, their resource utilization and trophic niche overlap probability were more similar in rural habitats than their natural counterparts. Our findings would be conducive to understand trophic niche and function variation in amphibians during the urbanization process, allowing for effective predictions of ecological consequences of habitat transformation. This study can also provide insight into conservation strategies for mountain amphibians in the Anthropocene.

关键词： amphibians habitat transformation habitat type stable isotopes trophic niche width urbanization

A New Species of the Genus Feirana(Amphibia:Anura:Dicroglossidae) from the Western Qinling Mountains of China

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Asian Herpetological Research 2011年第2期2卷 72-86页

作者： Xin YANG Bin WANG junhua hu Jianping JIANG Chengdu Institute of Biology Chinese Academy of Sciences Graduate University of Chinese Academy of Sciences

A new species, Feirana kangxianensis sp. nov., is described from the western Qinling Mountains in Gansu, China. Both morphological and molecular data support its validity. The new species is characterized by：（1） presence of keratinized nuptial spines on the thenar region of the hands in males of the new species, in contrast to F. taihangnica and F. quadranus; （2） of females, the ratios of UEW, INS, NSD and IPTL to SVL ofF. kangxianensis were significantly less than those of F. taihangnica and F. quadranus （P 〈 0.05）, while the ratio of IOS to SVL of the new species was significantly larger than that of the latter two species （P 〈 0.05）; and （3） of males, the ratios of INS, NSD, IPTW to SVL of the new species were significantly less than those ofF. taihangnica and F. quadranus （P 〈 0.05）, while the ratio of HL to SVL of the former was significantly larger than that of the latter, and the ratio of HW to SVL ofF. kangxianensis was significantly larger than that of F. taihangnica but less than that of F. quadranus, the ratio of OPTL to SVL of F. kangxianensis was significantly less than that of F. taihangnica but larger than that of F. quadranus （P 〈 0.05）. The three species of Feirana can be easily identified and significantly differ from each other by the canonical discriminant analyses with high correct classification （〉92%）. Concurrently, based on partial mitochondrial ND2 gene sequences, the result of the molecular phylogenetic analyses of the Feirana indicates that the F. kangxianensis is sister to F. taihangnica.

关键词： Feirana kangxianensis sp. nov. Dicroglossidae Kangxian Westem China

Planar Li growth on Li_(21)Si_(5)modified Li metal for the stabilization of anode

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Journal of Materials Science & Technology 2021年第17期76卷 156-165页

作者： Liuyang Cao Xue Cheng Hongjie Xu Guoqin Cao junhua hu Guosheng Shao School of Materials Science and Engineering Zhengzhou UniversityZhengzhou 450001China State Center for International Cooperation on Designer Low-Carbon&1 Environmental Materials(CDLCEM) Zhengzhou UniversityZhengzhou 450001China Zhengzhou Materials Genome Institute(ZMGI) Xingyang 450100China Institute for Renewable Energy and Environmental Technologies University of BoltonBolton BL35ABUK

Lithium(Li)metal is widely considered the ultimate anode for future rechargeable ***,dendritic growth and related parasitic reactions during long-term cycling often lead to severe safety hazards and catastrophic ***,we fabricate a hybrid anode by coating single-phase Li_(21)Si_(5)on lithium *** resultant electrodes show a stable cycle and depressed polarization in symmetric and half cells.A planar plating/stripping behavior is observed on the modified *** investigation of the interplay of Li and Li_(21)Si_(5)shows relatively large adsorption energy in the Li-Si *** deposition and stripping are surface processes,and Li_(21)Si_(5)maintains its intrinsic phase *** deposited Li layer around Li_(21)Si_(5)also has the advantage of diminished preferred orientation,which also contributes to the planar growth of *** LiFePO4(LFP)and LiNi1/3Co1/3 Mn1/3O2(NCM)cathodes were applied to further demonstrate the enhanced rate and cycle performance.

关键词： Lithium anode Planar growth Density functional theory Core-shell structure Adsorption energy