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Parameter estimation of maneuvering targets in OTHR based on sparse time-frequency representation

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Journal of Systems Engineering and Electronics 2016年第3期27卷 574-580页

作者： Jinfeng Hu Xuan He Wange li Hui Ai huiyong li Julan Xie School of Electronic Engineering University of Electronic Science and Technology of China

This paper proposes a new method for estimating the parameter of maneuvering targets based on sparse time-frequency transform in over-the-horizon radar（OTHR）. In this method, the sparse time-frequency distribution of the radar echo is obtained by solving a sparse optimization problem based on the short-time Fourier transform. Then Hough transform is employed to estimate the parameter of the targets. The proposed algorithm has the following advantages： Compared with the Wigner-Hough transform method, the computational complexity of the sparse optimization is low due to the application of fast Fourier transform（FFT）. And the computational cost of Hough transform is also greatly reduced because of the sparsity of the time-frequency distribution. Compared with the high order ambiguity function（HAF） method, the proposed method improves in terms of precision and robustness to noise. Simulation results show that compared with the HAF method, the required SNR and relative mean square error are 8 dB lower and 50 dB lower respectively in the proposed method. While processing the field experiment data, the execution time of Hough transform in the proposed method is only 4% of the Wigner-Hough transform method.

关键词： over-the-horizon radar(OTHR) maneuvering tar-get parameter estimation sparse time-frequency transform Hough transform

An Adaptive Task Creation Pruning Strategy for Optimizing Irregular Applications

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Chinese Journal of Electronics 2015年第3期24卷 535-541页

作者： CAO Qian li huiyong ZUO Min DENG Yun YU Yuan School of Computer and Information Engineering Beijing Technology and Business University School of Electronics Engineering and Computer Science Peking University College of Information Science and Engineering Guilin University of Technology

The Open MP task directive makes it possible to efficiently parallelize irregular applications, with task granularity as one of the most critical issues. To implement Open MP specification on multi-core architecture,a model is presented specializing in the execution of irregular applications. The model captures computation and communication within a node with host cores and accelerator cores. Based on this model, we propose an adaptive task creation pruning strategy including two stages to adjust dynamically task granularity. The first stage is task creation in breadth-first manner until getting to a threshold, which utilizes potential parallelism of multi-core processor. The second stage is starvation-triggered task regeneration once some worker thread becomes starved, which ensures work-stealing and thus achieves load balance. The evaluation is conducted with a series of typical irregular benchmarks, and the results indicate that our approach offers more effective performance in parallel execution of irregular benchmarks.

关键词： Task granularity Adaptive Irregular applications Multi-core

Decomposition mechanism of environmentally friendly insulating medium HFO1234zeE/N_(2)gas mixture under partial discharge

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High Voltage 2022年第6期7卷 1069-1079页

作者： lin lin Qingguo Chen Xinyu Wang Hui Zhang huiyong li Key Laboratory of Engineering Dielectrics and Its Application Ministry of EducationHarbin University of Science and TechnologyHarbinChina School of Electrical and Electronic Engineering Harbin University of Science and TechnologyHarbinChina Heilongjiang Institute for Drug Control Harbin HeilongjiangChina

Hydrofluoroolefin HFO1234zeE(trans-1,3,3,3-tetrafluoroprop-1-ene)is an environmentally friendly gas insulating medium that has the potential to replace *** clarify the decomposition paths and products of an HFO1234zeE/N_(2)gas mixture under partial discharge,the decomposition mechanism is explored with density functional *** results indicate that only HFO1234zeE molecules decompose in the range of low-temperature plasma,and electrons with different energies interact with molecules and cause them to decompose through different ***,products are generated by free radical recombination,addition reactions and internal configurational conversions of the *** experimental investigation of decomposition of the HFO1234zeE/N_(2)gas mixture with different discharge modes is carried out,and it is found that the products calculated with density functional theory are consistent with those seen *** results show the decomposition mechanism of the insulating gas under partial discharge and provide a theoretical basis for the application of HFO1234zeE.

关键词： theory. mixture mechanism

Cold Storage Capacity for Solar Air-Conditioning in Office Buildings in Different Climates

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Journal of Thermal Science 2019年第6期28卷 1195-1204页

作者： SUN Zhifeng ZHAO Yaohua XU Wei WANG Dongxu li huiyong ZHANG Xinyu li Huai li Yang College of Architecture and Civil Engineering Beijing University of TechnologyBeijing 100124China Institute of Building Environment and Energy China Academy of Building ResearchBeijing 100013China School of Civil and Resources Engineering University of Science and Technology BeijingBeijing 100083China Second Design Institute Beijing Institute of Architectural DesignBeijing 100045China

The building sector accounts for more than 40% of the global energy consumption. This consumption may be lowered by reducing building energy requirements and using renewable energy in building energy supply systems. Solar air-conditioning systems(SACS) are a promising solution for the reduction of conventional energy in buildings. The storage, especially the cold storage, plays an important role in SACS for unstable solar irradiation. In this paper, we took the absorption refrigerating unit as an example, and the solar air-conditioning system of an office building in Beijing was simulated. The accuracy of this model was verified by comparing with the SACS operation data. Moreover, based on the simulation data, the cold storage capacity of the solar air-conditioning system in different climatic regions was studied. The cold storage capacities of SACS in 20 cities distributed in different climate regions were studied systematically. The results simulated by our proposed model will be beneficial to the SACS design, and will enlarge the application of SACS.

关键词： office building solar air-conditioning system cold storage capacity TRNSYS

Design and optical performance investigation of all-sprayable ultrablack coating

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Nano Research 2023年第12期16卷 12901-12909页

作者： Chen Shen huiyong li Shuai Sun Hui Zhang Lanqin Yan Zhong Zhang CAS Key Laboratory of Nanosystem and Hierarchical Fabrication CAS Center for Excellence in NanoscienceNational Center for Nanoscience and TechnologyBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China Key Lab of Organic Optoelectronics and Molecular Engineering of Ministry of Education Laboratory of Flexible Electronics Technology Department of ChemistryTsinghua UniversityBeijing 100084China CAS Key Laboratory of Mechanical Behavior and Design of Materials Department of Modern MechanicsUniversity of Science and Technology of ChinaHefei 230027China

Although ultrablack surfaces are urgently needed in wide applications owing to their extremely low reflectance over a broadband wavelength,obtaining simultaneously the ultrablackness and mechanical robustness by simple process technique is still a great ***,by decoupling different light extinction effects to different layers of coating,we design an ultrablack coating that is all-sprayable in whole *** coating presents low reflectance over visible–mid-infrared(VIS–MIR)wavelength(av.R≈1%in VIS),low multi-angle scattering(bidirectional reflection distribution function(BRDF)=10-2–10-3 sr-1),together with good substrate adhesion grade and self-cleaning ability,which are superior to most reported sprayable ultrablack *** light extinction effects of each layer are *** method is also applicable in other material systems.

关键词： ultrablack spray-coating carbon nanomaterials multiple scattering intermediate layer

Simultaneous acquisition of Fe3O4 monocrystals:Tunable magnetic properties with various morphologies

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Progress in Natural Science:Materials International 2020年第1期30卷 41-46页

作者： Zemin Zheng Yiming Cao Zhe li huiyong li Dafeng Hu Hao Jiang Xuemin Geng Jiangwei Lu Xudong Zhang Peng Yang Yanfen Wan School of Materials Science and Engineering Yunnan Key Laboratory for Micro/nano Materials & TechnologyYunnan University Center for Magnetic Materials and Devices & Key Laboratory for Advanced Functional and Low Dimensional Materials of Yunnan Higher Education Institute Qujing Normal University

Fe3O4nanoparticles（NPs） with a face-centered cubic（fcc） structure and two different morphologies（nanospheres and nanoprisms） were synthesized by a facile one-step *** synthesized Fe3O4nanospheres and nanoprisms were monocrystalline and separable in a magnetic *** different volume ratios of oleylamine（OAm） to dibenzyl ether,the sizes of the prepared Fe3O4NPs ranged from 5 to 21 *** OAm amount in the synthesis can significantly control the morphology of *** the OAm content increased from 10 ml to 30 ml,the faceted nanoprisms shrank while the nanospheres *** an OAm content of 25 ml,the nanoprisms diminished while more hexagonal and sphere-like particles appeared,implying a critical point of morphology transition from triangle to *** magnetic properties also depended on the NP morphology and *** prepared Fe3O4NPs are promising candidates in medical applications such as magnetic resonance imaging,targeted drug delivery,blood purification,and tumor hyperthermia.

关键词： Fe 3 O 4 Nanoparticles Nanoprism Nanosphere Superparamagnetic

Enhancing phosphorus uptake efficiency through QTL-based selection for root system architecture in maize

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Journal of Genetics and Genomics 2016年第11期43卷 663-672页

作者： Riliang Gu Fanjun Chen lizhi Long Hongguang Cai Zhigang liu Jiabo Yang lifeng Wang huiyong li Junhui li Wenxin liu Guohua Mi Fusuo Zhang lixing Yuan Key Lab of Plant-Soil Interaction MOECenter for ResourcesEnvironment and Food SecurityCollege Resources and Environmental SciencesChina Agricultural University College of Agronomy and Biotechnology China Agricultural University Institute of Agricultural Resource and Environment Jilin Academy of Agricultural Sciences Cereal Crops Research Institute Henan Academy of Agricultural Sciences

Root system architecture （RSA） plays an important role in phosphorus （P） acquisition, but enhancing P use efficiency （PUE） in maize via genetic manipulation of RSA has not yet been reported. Here, using a maize recombinant inbred line （RIL） population, we investigated the genetic relationships between PUE and RSA, and developed P-efficient lines by selection of quantitative trait loci （QTLs） that coincide for both traits. In low-P （LP） fields, P uptake efficiency （PupE） was more closely correlated with PUE （r = 0.48 -0.54）, and RSA in hydroponics was significantly related to PupE （r=0.25-0.30） but not to P utilization efficiency （PutE）. QTL analysis detected a chromosome region where two QTLs for PUE, three for PupE and three for RSA were assigned into two QTL clusters, Cl-bin3.04a and Cl-bin3.04b. These QTLs had favorable effects from alleles derived from the large-rooted and high-PupE parent. Marker-assisted selection （MAS） identified nine advanced backcross-derived lines carrying Cl-bin3.04a or Cl-bin3.04b that displayed mean increases of 22%-26% in PUE in LP fields. Furthermore, a line L224 pyramiding Cl- binB.04a and Cl-bin3.04b showed enhanced PupE, relying mainly on changes in root morphology, rather than root physiology, under both hydroponic and field conditions. These results highlight the physiological and genetic contributions of RSA to maize PupE, and provide a successful study case of developing P-efficient crops through QTL-based selection.

关键词： Maize Quantitative trait loci Phosphorus Root system architecture Marker-assisted selection

Fabricating bio-inspired high impact resistance carbon nanotube network films for multi-protection under an extreme environment

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Nano Research 2024年第9期17卷 7793-7802页

作者： Mingquan Zhu Kailu Xiao Wei Zhang Xudong Lei Yunxiang Bai Shijun Wang Peng Zhang Feng Gao Congying Wang Wenqiang Xu huiyong li Xianqian Wu Chao Wang Hui Zhang Luqi liu Zhong Zhang CAS Key Laboratory of Nanosystem and Hierarchical Fabrication CAS Center for Excellence in NanoscienceNational Center for Nanoscience and TechnologyBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China Department of Materials Science and Engineering Texas A&M UniversityCollege StationTexas 77840USA Institute of Mechanics Chinese Academy of SciencesBeijing 100190China School of Astronautics Harbin Institute of TechnologyHarbin150001China CAS Key Laboratory of Mechanical Behavior and Design of Materials Department of Modern MechanicsUniversity of Science and Technology of ChinaHefei 230027China

The fabrication of light-weight,highly impact-resistant,and energy-absorbent materials is urgently demanded in many facets of the society from body armor to aerospace engineering,especially under an extreme *** nanotubes(CNTs),one of the strongest and toughest materials ever found,also have good conductivity,chemical stability,and thermal stability,etc,making them a competitive candidate as building blocks to help achieve the above *** this work,a kind of CNT network was prepared by using chlorosulfonic acid(CSA)to release the internal stress of super-aligned carbon nanotube films(SA-CNTF)and dendritic polyamide amine(PAMAM)to further introduce multiple hydrogen bonds and interlocking *** fabricated bioinspired carbon nanotube network films(PAMAM@C-CNTF)have a high toughness of 45.97 MJ/m3,showing an increase of 420%compared to neat *** importantly,the anti-impact performance of the films(e.g.,with a maximum specific energy absorption of 1.40 MJ/kg under 80-100 m/s projectile impact)is superior to that of conventional protective materials from steel and Kevlar fiber,and also exceeds that of any other reported carbon-based *** hierarchical energy dissipation mechanism was further revealed through experiment and *** functions including intelligent heating/anti-icing,ultraviolet protection,as well as electromagnetic interference shielding properties make these network films have great potential in practical multi-protection applications,especially under an extreme environment.

关键词： carbon nanotubes composites mechanical properties multi-function

Osmotic Stress Resistance of Transgenic Tobacco Expressed Soybean Lysine-rich Protein Gene

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Journal of Northeast Agricultural University(English Edition) 2010年第1期17卷 43-47页

作者： li Peiqing SHUANG Bao JIA huiyong LV Yang li Jie College of life Sciences Northeast Agricultural University Harbin 150030 China

PM2 gene （accession number： M80664） with high lysine content from soybean （Glycine max） was found in GenBank by changing three BLASTp parameters. Amino acid composition analysis of PM2 showed that Lys content was on the high level of 18.22%. Protein encoded by PM＇2 also belonged to the family of late embryogenesis abundant （LEA） proteins, which was considered that it had a strong relation with the abiotic stress resistance. In this experiment, PM2 gene was obtained from dry soybean seeds by RT-PCR, plant expression vector pEMTPM2 was constructed, and then transformed into tobacco by using agrobacterium-mediated method. Eight salt and drought tolerant lines were obtained from 31 differentiated lines. Real-time PCR showed that PM2 gene overexpressed in all four PCR positive lines with the osmotic stress resistance. These results confirmed that the overexpression of PM2 gene enhanced the osmotic stress resistance of transgenic tobacco.

关键词： PM2 gene lysine-rich protein LEA protein osmotic stress resistance