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LPV Flight Dynamics Modeling for Turbulent Wind Special Flight Analysis

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Transactions of Nanjing University of Aeronautics and Astronautics 2018年第3期35卷 464-471页

作者： gao Zhenxing hu Jinshuo College of Civil Aviation Nanjing University of Aeronautics and Astronautics

A linear parameter varying(LPV)flight dynamics model(FDM)is proposed to cater for atmospheric disturbance analysis in special flight conditions.A novel FDM which is capable of addressing the influence of turbulent wind is derived under the wind *** affine parameter dependent LPV model with wind effects is built based on function substitution *** optimal solution for the decomposing function of the LPV FDM is obtained by genetic algorithm(GA).The analysis of dynamic response indicates that the genetic-optimized LPV FDM approximates the nonlinear FDM evidently,since it identifies the instantaneous dynamics and flight states varying in a wide *** simulations of approach and landing against wind shear show that the genetic-optimized LPV FDM captures the instantaneous dynamic response when flying through turbulent wind,indicating that the LPV model can be further applied to turbulent wind special flight analysis and control law design.

关键词： linear parameter varying function substitution genetic algorithm wind shear atmospheric disturbance

Bioinspired Polarized Skylight Orientation Determination Artificial Neural Network

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Journal of Bionic Engineering 2023年第3期20卷 1141-1152页

作者： huaju Liang Hongyang Bai ke hu Xinbo Lv School of Energy and Power Engineering Nanjing University of Science and TechnologyNanjing210094China Neuromorphic Computing Laboratory China Nanhu Academy of Electronics and Information TechnologyJiaxing314001China Guidance Radar General Department Xi’an Electronic Engineering Research InstituteXi’an710100China School of Automation Nanjing University of Science and TechnologyNanjing210094China

This paper proposes an artificial neural network to determine orientation using polarized skylight. This neural network has specific dilated convolution, which can extract light intensity information of different polarization directions. Then, the degree of polarization (DOP) and angle of polarization (AOP) are directly extracted in the network. In addition, the exponential function encoding of orientation is designed as the network output, which can better reflect the insect’s encoding of polarization information and improve the accuracy of orientation determination. Finally, training and testing were conducted on a public polarized skylight navigation dataset, and the experimental results proved the stability and effectiveness of the network.

关键词： Polarized light navigation Orientation determination Artificial neural network

Microstructure,Mechanical Properties and Texture Evolution of Mg-Al-Zn-La-Gd-Y Magnesium Alloy by Hot Extrusion and Multi-Pass Rolling

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Acta Metallurgica Sinica(English Letters) 2020年第10期33卷 1359-1368页

作者： Qiyu Liao Wenxin hu Qichi Le Xingrui Chen ke hu Chunlong Cheng Chenglu hu key Lab of Electromagnetic Processing of Materials Ministry of EducationNortheastern UniversityShenyang 110819China Baotou Research Institute of Rare Earths Baotou 014000China

A high-ductility Mg-8.10Al-0.42Zn-0.51Mn-1.52La-1.10Gd-0.86 Y(wt%)alloy was developed by hot extrusion and multi-rolling *** between microstructure,mechanical properties and texture evolution of the extruded and rolled alloy were *** rolling process had significant effect on grain refinement of the extruded *** grain size reduced from 12.3 to 4.9μm with the increasing rolling *** the increase in rolling pass,the proportion of dynamic recrystallized(DRXed)grains increases due to particle-stimulated nucleation,grain boundary nucleation and twin induced *** the process of multiple rolling,the basal pole gradually tilted from normal direction to transverse direction due to the asymmetric deformation and irregular grain deformation,resulting in the weakening of the base *** results showed that grain refinement and texture weakening were the main reasons for the good ductility of the alloy.

关键词： Extrusion Multi-rolling Grain refinement Texture evolution Mechanical properties

An Efficient Boron Source Activation Strategy for the Low‑Temperature Synthesis of Boron Nitride Nanotubes

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Nano-Micro Letters 2025年第1期17卷 548-558页

作者： Ying Wang Kai Zhang Liping Ding Liyun Wu Songfeng E Qian He Nanyang Wang hui Zuo Zhengyang Zhou Feng Ding Yue hu Jin Zhang Yagang Yao National Laboratory of Solid State Microstructures College of Engineering and Applied SciencesJiangsu Key Laboratory of Artificial Functional Materialsand Collaborative Innovation Center of Advanced MicrostructuresNanjing UniversityNanjing 210093People’s Republic of China School of Electronic Information and Artificial Intelligence Shaanxi University of Science&TechnologyXian 710000People’s Republic of China College of Bioresources Chemical and Materials Engineering Shaanxi University of Science&TechnologyXian 710000People’s Republic of China key Laboratory of Carbon Materials of Zhejiang Province College of Chemistry and Materials EngineeringWenzhou UniversityWenzhou 325000People’s Republic of China Shenzhen Institutes of Advanced Technology Chinese Academy of SciencesShenzhen 518000People’s Republic of China College of Chemical and Molecular Engineering Peking UniversityBeijing 100871People’s Republic of China

Lowering the synthesis temperature of boron nitride nanotubes(BNNTs)is crucial for their *** primary reason for adopting a high temperature is to enable the effective activation of highmelting-point solid *** this study,we developed a novel approach for efficiently activating boron by introducing alkali metal compounds into the conventional MgO–B *** approach can be adopted to form various low-melting-point AM–Mg–B–O growth *** growth systems have improved catalytic capability and reactivity even under low-temperature conditions,facilitating the synthesis of BNNTs at temperatures as low as 850℃.In addition,molecular dynamics simulations based on density functional theory theoretically demonstrate that the systems maintain a liquid state at low temperatures and interact with N atoms to form BN *** findings offer novel insights into the design of boron activation and are expected to facilitate research on the low-temperature synthesis of BNNTs.

关键词： Boron nitride nanotubes Low-temperature Boron activation Density functional theory

Selenylation Modification of Degraded Polysaccharide from Enteromorpha prolifera and Its Biological Activities

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Journal of Ocean University of China 2018年第2期17卷 445-450页

作者： LV Haitao DUAN ke SHAN hu College of Chemistry and Pharmaceutical Sciences Qingdao Agricultural University College of Animal Science and Technology Qingdao Agricultural University

Polysaccharide extracted from Enteromorpha prolifera possessed excellent biological activities,but its molecular weight was greatly high which influenced the *** Se had higher biological activities and was safer than inorganic Se *** the present study,Enteromorpha polysaccharide was degraded to low molecular weight by free-radical degradation method of H_2O_2 and ascorbic *** single factor and orthogonal experiments,the optimal degradation conditions were reaction time of 2 h,reaction temperature of 50℃,H_2O_2/ascorbic acid(n/n=1:1)concentration of 15 mmol L^(-1),and solid-liquid ratio of 1:50(g mL^(-1)).Then,the degraded polysaccharide was chemically modified to obtain its selenide derivatives by nitric acid-sodium selenite *** selenium content was 1137.29μg g^(-1),while the content of sulfate radical had no *** spectra indicated that the selenite ester group was *** polysaccharide selenide was characterized and evaluated for antioxidant,antifungal and antibacterial *** results showed that degraded polysaccharide selenide had strong capacity of scavenging DPPH and·OH free *** had significant antibacterial properties for Escherichia coli,Bacillus subtilis and Salmonella spp.,and it also had significant antifungal properties for Apple *** result ascertained degradation and selenylation modification did not change the main structure of *** was possible that free-radical degradation was an effective way for enhancing antioxidant activity to decrease molecular weight of polysaccharides.

关键词： Enteromorpha prolifera polysaccharide free-radical degradation selenylation modification biological activity

Exact Boundary Controllability and Exact Boundary Observability for a Coupled System of Quasilinear Wave Equations

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Chinese Annals of Mathematics,Series B 2013年第4期34卷 479-490页

作者： Long hu Fanqiong JI ke WANG School of Mathematical Sciences Fudan University

Based on the theory of semi-global classical solutions to quasilinear hyperbolic systems, the authors apply a unified constructive method to establish the local exact boundary(null) controllability and the local boundary(weak) observability for a coupled system of 1-D quasilinear wave equations with various types of boundary conditions.

关键词： Coupled system of quasilinear wave equations Exact boundary control-lability Exact boundary observability

Ecological Network Analysis Quantifying the Sustainability of Regional Economies: A Case Study of Guangdong Province in China

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Chinese Geographical Science 2018年第1期28卷 127-136页

作者： LIANG Jinshe hu ke DAI Teqi Faculty of Geographical Science Beijing Normal University

To meet the challenge of sustainable development, sustainability must be made. Ecological network analysis(ENA) was introduced in this paper as an approach to quantitatively measure the growth, development, and sustainability of an economic system. The Guangdong economic networks from 1987 to 2010 were analyzed by applying the ENA approach. Firstly, a currency flow network among economic sectors was constructed to represent the Guangdong economic system by adapting the input-output(I-O) table data. Then, the network indicators from the ENA framework involving the total system throughput(TST), average mutual information(AMI), ascendency(A), redundancy(R) and development capacity(C) were calculated. Lastly, the network indicators were analyzed to acquire the overall features of Guangdong's economic operations during 1987–2010. The results are as follows: the trends of the network indicators show that the size of the Guangdong economic network grows exponentially at a high rate during 1987–2010, whereas its efficiency does not present a clear trend over its whole period. The growth is the main characteristic of the Guangdong economy during 1987–2010, with no clear evidence regarding its development. The quantitative results of the network also confirmed that the growth contributed to a great majority of the Guangdong economy during 1987–2010, whereas the development's contribution was tiny during the same period. The average value of the sustainability indicator(α) of the Guangdong economic network was 0.222 during 1987–2010, which is less than the theoretically optimal value of 0.37 for a sustainable human-influenced system. The results suggest that the Guangdong economic system needs a further autocatalysis to improve its efficiency to support the system maintaining a sustainable evolvement.

关键词： network analysis regional economy sustainability evaluation ascendency Guangdong Province of China

Promoting CO_(2) and H_(2)O activation on O-vacancy regulated In-Ti dual-sites for enhanced CH_(4) photo-production

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Journal of Energy Chemistry 2023年第11期86卷 599-608,I0013页

作者： Cong Chen Liang Chen Yangguang hu ke Yan Ting Wang Youju huang Chao gao Junjie Mao Shoujie Liu Benxia Li School of Chemistry and Chemical Engineering Key Laboratory of Surface&Interface Science of Polymer Materials of Zhejiang ProvinceZhejiang Sci-Tech UniversityHangzhou 310018ZhejiangChina College of Material Chemistry and Chemical EngineeringKey Laboratory of Organosilicon Chemistry and Material TechnologyMinistry of EducationHangzhou Normal UniversityHangzhou 311121ZhejiangChina School of Chemistry and Materials Science University of Science and Technology of ChinaHefei 230026AnhuiChina key Laboratory of Functional Molecular Solids Ministry of EducationCollege of Chemistry and Materials ScienceAnhui Normal UniversityWuhu 241002AnhuiChina School of Materials Science and Engineering Anhui UniversityHefei 230601AnhuiChina

Engineering the specific active sites of photocatalysts for simultaneously promoting CO_(2)and H_(2)O activation is important to achieve the efficient conversion of CO_(2)to hydrocarbon with H_(2)O as a proton source under ***,we delicately design the In/TiO_(2)-VOphotocatalyst by engineering In single atoms(SAs)and oxygen vacancies(VOs)on porous TiO_(2).The relation between structure and performance of the photocatalyst is clarified by both experimental and theoretical analyses at the atomic *** In/TiO_(2)-VOphotocatalyst furnish a high CH_(4)production rate up to 35.49μmol g^(-1)h^(-1)with a high selectivity of 91.3%under simulated sunlight,while only CO is sluggishly generated on TiO_(2)-*** combination of in situ spectroscopic analyses with theoretical calculations reveal that the VOsites accelerate H_(2)O dissociation and increase proton feeding for CO_(2)***,the VOregulated In-Ti dual sites enable the formation of a stable adsorption conformation of In-C-O-Ti intermediate,which is responsible for the highly selective reduction of CO_(2)to CH_(4).This work demonstrates a new strategy for the development of effective photocatalysts by coupling metal SA sites with the adjacent metal sites of support to synergistically enhance the activity and selectivity of CO_(2)photoreduction.

关键词： In single atoms Oxygen vacancies CO_(2) photoreduction Water dissociation Synergetic effect

纤维素降解菌I2的分离及相关降解基因功能验证

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食品与发酵工业 2025年第1期51卷 47-54页

作者：孙君珂张婉莹邓若竹王娟牛秋红胡凡柯涛南阳师范学院生命科学与农业工程学院河南省生物质资源化高校工程中心河南南阳473000 自然资源部第三海洋研究所福建厦门361000

纤维素是地球上数量最大的可再生能源物质,利用微生物或其产生的酶可将纤维素水解成葡萄糖。筛选高效纤维素降解菌和纤维素酶一直是生物能源等领域研究的热点。该研究筛选分离了1株具有降解纤维素能力的短小芽孢杆菌I2,通过基因组测序,... 详细信息

纤维素是地球上数量最大的可再生能源物质,利用微生物或其产生的酶可将纤维素水解成葡萄糖。筛选高效纤维素降解菌和纤维素酶一直是生物能源等领域研究的热点。该研究筛选分离了1株具有降解纤维素能力的短小芽孢杆菌I2,通过基因组测序,分析其参与纤维素降解的基因,并对纤维素酶的功能进行验证。I2分离自河南南阳宝天曼自然保护区落叶及长期堆积小麦秸秆的堆体等样本富集后的混合菌系,具有降解滤纸的能力,48 h内可以降解大部分滤纸。基因组组装分析显示,I2的基因组大小为4.2 Mbp,含有4635个基因。利用CAZy碳水化合物数据库注释和酶活性测定实验,对数据库检测到的182个基因进行分析,明确I2中4个基因在大肠杆菌表达后具有纤维素酶活性。其中,G2269纤维素内切酶活性最高,在pH 5.0,温度55℃条件下,酶活力可达49.02 U/mL。金属离子Ca^(2+)、Zn^(2+)对于G2269的活性有明显提高作用,Mn^(2+)和Cu^(2+)对G2269活性抑制比较明显,Mg^(2+)、Co^(2+)、K+、Ni^(2+)、NH 4+对于G2269的活性无显著影响。此外,G2269还具有良好热稳定性和酸碱稳定性,在65℃保持30 min后仍保留70%的活力,在食品加工和饲料生产等领域显示出较好的应用潜力。

关键词：纤维素降解菌基因克隆原核表达基因组测序