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基于系统工程的航空电子系统深度综合化需求分析与评估方法

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航空电子技术 2024年第1期55卷 1-8页

作者：黄俊张正勇方学立 93184部队北京100076

本文在分析综合化航空电子系统使用和信息流转的基础上,提出了一种综合化航空电子系统需求分析及评估方法。该方法从信息获取能力、传输能力、处理能力、显示能力和任务能力等方面建立评估模型,基于层次分析法设计能力需求仿真评估系统... 详细信息

本文在分析综合化航空电子系统使用和信息流转的基础上,提出了一种综合化航空电子系统需求分析及评估方法。该方法从信息获取能力、传输能力、处理能力、显示能力和任务能力等方面建立评估模型,基于层次分析法设计能力需求仿真评估系统,并以基于模型的系统需求分析为输入对航空电子系统的能力需求进行评估,为综合化航空电子系统需求的分析与评估提供了参考。

关键词：综合化航空电子系统需求分析评估模型

θ-Type Derivation and Derivation Superalgebra of the Finite-Dimensional Modular Lie Superalgebra W（m, n, l, t_）

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Journal of Mathematical Research and Exposition 2008年第2期28卷 297-304页

作者： FANG Xiao Chao zhang yong zheng Department of Mathematics Harbin College Heilongjiang 150080 China Department of Mathematics Northeast Normal University Jilin 130024 China

In this paper F always denotes a field of characteristic p 〉 2. We construct the finitedimensional modular Lie superalgebra W（m,n, l, t_） over a field F, define θ-type derivation and determine the derivation super... 详细信息

关键词： modular Lie superalgebra generator derivation.

Using the Phosphomannose Isomerase (PMI) Gene from Saccharomyces cerevisiae for Selection in Rice Transformation

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Journal of Integrative Agriculture 2012年第9期11卷 1391-1398页

作者： WANG Tao LIU Liang-yu TANG yong-yan zhang Xiao-bo zhang Mei-dong zheng yong-lian zhang Fang-dong National Key Laboratory of Crop Genetic Improvement Ministry of Science and Technology/Huazhong Agricultural University Wuhan 430070P. R. China

The phosphomannose isomerase （PMI） gene from Saccharomyces cerevisiae acted as selectable marker and mannose acted as selective agent for the production of transgenic plants of rice （Oryza sativa L.） via Agrobacterium-mediated transformation. The concentration of mannose during the selection was stepwise increased, 5 g L-1 mannose combined with 15 g L-1 sucrose and 500 mg L-1 cefotaxime was used in the initial selection stage, then the concentration of mannose was increased to 11 g L-1, the highest transformation rate was 20.0%. The integration of PMI gene was confirmed by PCR, and the result of RT-PCR assay proved that the intron of PMI gene can be excised correctly during RNA splicing. 13- Glucuronidase （GUS） activity analysis confirmed the expression of GUS gene. All those means the PMI gene from yeast can be used as a selectable marker in rice transformation.

关键词： phosphomannose isomerase selectable marker Saccharomyces cerevisiae transformation rice

Precipitation scale effect of the TRMM satellite in Tianshan,China

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Journal of Mountain Science 2023年第5期20卷 1349-1368页

作者： NING Shan ZHOU Hong-wu zhang zheng-yong BAI Shi-biao LIU Lin College of Marine Sciences and Engineering Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and ApplicationNanjing Normal UniversityNanjing 210000China College of Sciences Shihezi UniversityShihezi 832000China

High-resolution precipitation data is conducive to objectively describe the spatial-temporal variability of regional precipitation,and the study of downscaling techniques and spatial scale effects can provide technical and theoretical support to improve the spatial resolution and accuracy of satellite precipitation *** this study,we used a machine learning algorithm combined with a regression algorithm RF-PLS(Random Forest-Partial Least Squares)to construct a downscaling model to obtain three types of high-resolution TRMM(Tropical Rainfall Measuring Mission)downscaled precipitation data for the years 2000-2017 at 250 m,500 m,and *** scale effects with topographic and geomorphological features in the study area were ***,we described the spatial and temporal variation of precipitation based on the optimal TRMM downscaled precipitation *** results showed that:1)The linear relationships between the TRMM downscaled precipitation data obtained by each of the three downscaled models(PLS,RF,and RF-PLS)and the precipitation at the observation stations were improved compared to the linear relationships between the original TRMM data and the precipitation at the observation *** accuracy of the RF-PLS model was better than the other two models.2)Based on the RF-PLS model,the resolution of the TRMM data was increased to three different scales(250 m,500 m,and 1 km),considering the scale effects with topographic and geomorphological *** precipitation simulation effect with a spatial resolution of 500 m was better than the other two scales.3)The annual precipitation was the highest in the areas with extremely high mountains,followed by the mediumhigh mountain,high mountain,medium mountain,medium-low mountain,plain,low mountain,and basin.

关键词： TRMM data Scale effect Landform Tianshan Mountains

Exploring Trade-offs in Thermal Interface Materials:The Impact of Polymer-Filler Interfaces on Thermal Conductivity and Thixotropy

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Chinese Journal of Polymer Science 2024年第7期42卷 916-925,I0006页

作者： Bin zhang zheng-Li Dou yong-zheng zhang Qiang Fu Kai Wu College of Polymer Science and Engineering State Key Laboratory of Polymer Materials EngineeringSichuan UniversityChengdu610065China

Effective thermal transport across solid-solid interfaces which is essential in thermal interface materials(TIMs),necessitates both optimal thixotropy and high thermal *** role of filler surface modification,a fundamental aspect of TIM fabrication,in the influence of these properties is not fully *** study employs the use of a silane coupling agent(SCA)to modify alumina,integrating experimental approaches with molecular dynamics simulations,to elucidate the interface effects on thixotropy and thermal conductivity in polydimethylsiloxane(PDMS)-based *** findings reveal that the variations of SCAs modify both interface binding energy and transition layer *** interface binding energy restricts macromolecular segmental relaxation near the interface,hindering desirable thixotropy and bond line *** the contrary,the thickness of the transition layer at the interface positively influences thermal conductivity,facilitating the transport of phonons between the polymer and ***,selecting an optimal SCA allows a balance between traditionally conflicting goals of high thermal conductivity and minimal bond line thickness,achieving an impressively low interface thermal resistance of just 2.45-4.29 K·mm^(2)·W^(-1)at275.8 kPa.

关键词： Thermal interface material Surface modification Thermal conductivity Thixotropy Interface thermal resistance

Community structure and regeneration types of Betula dahurica forest in Badaling forest center of Beijing

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Forestry Studies in China 2007年第2期9卷 152-156页

作者： zhang yong zheng Zhi-hua zhang Zhi-xiang College of Biological Sciences and Biotechnology Beijing Forestry University Beijing 100083 P. R. China

Using plant community analysis methods, we analyzed the floristic characteristics, species composition, community structure, population structure, and spatial distribution patterns of a Betula dahurica forest on the ＂1238＂ mountain of Badaling in Beijing, China. The results show that： 1） There are 33 plant species in the B. dahurica community, including 18 woody plant species. The B. dahurica forest is a monodominant community with 75.9% dominance. 2） Based on diameter at breast height （DBH） size class distribution, the population structure of B. dahurica and Acer mono--two heliophyllous and pioneer tree species-is cascade-type, with both in an increasing stage. The population structure of Ella mandshurica and T. mongolica, two shade-tolerant tree species, is inverse-J type, and they have more young seedling individuals and regenerate more stably. They are associated species of the pioneer tree species. The population structure of Quercus mongolica, as the associated species of climax species in the community, is sporadic, and its regeneration is fluctuating and random. Fraxinus rhynchophylla is a shade-tolerant tree species which has a unibar population structure and climax characteristics of pioneer tree species. The relative frequency of young seedlings reached 0.4. 3） The dominant species B. dahurica is still in an increasing stage, and the regeneration of other species is steady or partly influences the community, putting the community in the pioneer species stage. From the population structure and distribution frequency ofF. rhynchophylla, the B. dahurica forest will approach to a climax state in the future.

关键词： Betula dahurica forest community structure population structure regeneration type

Immunobiology of COVID-19: Mechanistic and therapeutic insights from animal models

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Zoological Research 2024年第4期45卷 747-766页

作者： Hong-Yi zheng Tian-zhang Song yong-Tang zheng State Key Laboratory of Genetic Evolution&Animal Models KIZ-CUHK Joint Laboratory of Bioresources and Molecular Research in Common DiseasesCenter for Biosafety Mega-ScienceKunming Institute of ZoologyChinese Academy of SciencesKunmingYunnan 650223China National Resource Center for Non-Human Primates National Research Facility for Phenotypic&Genetic Analysis of Model Animals(Primate Facility)Kunming Institute of ZoologyChinese Academy of SciencesKunmingYunnan 650107China

The distribution of the immune system throughout the body complicates in vitro assessments of coronavirus disease 2019(COVID-19)immunobiology,often resulting in a lack of reproducibility when extrapolated to the whole ***,developing animal models is imperative for a comprehensive understanding of the pathology and immunology of severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)*** review summarizes current progress related to COVID-19 animal models,including non-human primates(NHPs),mice,and hamsters,with a focus on their roles in exploring the mechanisms of immunopathology,immune protection,and long-term effects of SARS-CoV-2 infection,as well as their application in immunoprevention and immunotherapy of SARS-CoV-2 *** among these animal models and their specific applications are also highlighted,as no single model can fully encapsulate all aspects of *** effectively address the challenges posed by COVID-19,it is essential to select appropriate animal models that can accurately replicate both fatal and non-fatal infections with varying courses and *** animal model libraries and associated research tools is key to resolving the global COVID-19 pandemic,serving as a robust resource for future emerging infectious diseases.

关键词： SARS-CoV-2 COVID-19 Animal models Infection immunology Immunotherapy

A High-Accuracy Curve Boundary Recognition Method Based on the Lattice Boltzmann Method and Immersed Moving Boundary Method

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Computer Modeling in Engineering & Sciences 2024年第9期140卷 2533-2557页

作者： Jie-Di Weng yong-zheng Jiang Long-Chao Chen Xu zhang Guan-yong zhang Hunan Provincial Key Laboratory of Health Maintenance for Mechanical Equipment Hunan University of Science and TechnologyXiangtan411201China School of Mechanical Engineering Hunan Chemical Vocational Technology CollegeZhuzhou412000China

Applying numerical simulation technology to investigate fluid-solid interaction involving complex curved bound-aries is vital in aircraft design,ocean,and construction ***,current methods such as Lattice Boltzmann(LBM)and the immersion boundary method based on solid ratio(IMB)have limitations in identifying custom curved ***,IBM based on velocity correction(IBM-VC)suffers from inaccuracies and numerical ***,this study introduces a high-accuracy curve boundary recognition method(IMB-CB),which identifies boundary nodes by moving the search box,and corrects the weighting function in LBM by calculating the solid ratio of the boundary nodes,achieving accurate recognition of custom curve *** addition,curve boundary image and dot methods are utilized to verify *** findings revealed that IMB-CB can accurately identify the boundary,showing an error of less than 1.8%with 500 ***,the flow in the custom curve boundary and aerodynamic characteristics of the NACA0012 airfoil are calculated and compared to *** showed that IMB-CB yields lower lift and drag coefficient errors than IBM-VC,with a 1.45%drag coefficient *** addition,the characteristic curve of IMB-CB is very stable,whereas that of IBM-VC is *** the moving boundary problem,LBM-IMB-CB with discrete element method(DEM)is capable of accurately simulating the physical phenomena of multi-moving particle flow in complex curved *** research proposes a new curve boundary recognition method,which can significantly promote the stability and accuracy of fluid-solid interaction simulations and thus has huge applications in engineering.

关键词： Fluid-solid interaction curve boundary recognition method Lattice Boltzmann method immersed moving boundary method

Influence of Micro/Nano-Ti Particles on the Corrosion Behavior of AZ31-Ti Composites

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Acta Metallurgica Sinica(English Letters) 2024年第3期37卷 484-498页

作者： Jinchao Jiao Jin zhang yong Lian Shengli Han Kaihong zheng Fusheng Pan Institute for Advanced Materials and Technology University of Science and Technology BeijingBeijing 10083China Beijing Key Laboratory for Corrosion Erosion and Surface Technology Beijing 100083China Institute of New Materials Guangdong Academy of SciencesGuangzhou 510650China National Engineering Research Center for Magnesium Alloys Chongqing UniversityChongqing 404100China

Adding Ti particles to magnesium alloy simultaneously enhances its strength and ***,how these particles influence on Mg alloy’s corrosion performance is seldom *** corrosion behavior of AZ31-Ti composites containing titanium nanoparticles(1.5 and 5 wt%)and micron particles(10 wt%)prepared by powder metallurgical in 3.5 wt%NaCl solution was *** results indicate that Ti particles serve as the primary location for the cathodic hydrogen reduction reaction,resulting in intense galvanic corrosion between the Ti and Mg *** nanoparticles distributed at the interface of the original AZ31 powder were in a discontinuous mesh structure,thus failing to act as a barrier against *** corrosion products with the existence of numerous cracks gradually peel off during the corrosion process and cannot protect the *** average corrosion rate P_(w) of AZ31,AZ31-1.5%Ti,AZ31-5%Ti,and AZ31-10%Ti after 7 days of immersion is 27.55,105.65,283.67,and 99.35 mm/y,***,AZ31-Ti composites can be considered as potential candidates for degradable fracturing ***,it is recommended to improve their corrosion resistance through surface treatment.

关键词： AZ31-Ti composite Nano-Ti Micro-Ti Corrosion behavior Scanning Kelvin probe force microscopy(SKPFM)