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Dynamic Analysis and Parametric Optimization of Telescopic Tubular Mast Applied on Solar Sail

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Chinese Journal of Mechanical Engineering 2023年第2期36卷 279-290页

作者： Chenyang Ji Jinguo Liu Chenchen Wu pengyuan zhao Keli Chen State Key Laboratory of Robotics Shenyang Institute of AutomationChinese Academy of ScienceShenyang 110016China Institutes for Robotics and Intelligent Manufacturing Chinese Academy of SciencesShenyang 110169China School of Mechanical Engineering and Automation Northeastern UniversityShenyang 110819China University of Chinese Academy of Sciences Beijing 100049China

Large-scale solar sails can provide power to spacecraft for deep space exploration.A new type of telescopic tubular mast(TTM)driven by a bistable carbon fiber-reinforced polymer tube was designed in this study to solve the problem of contact between the sail membrane and the spacecraft under light *** with the traditional TTM,it has a small size,light weight,high extension ratio,and simple *** anti-blossoming and self-unlocking structure of the proposed TTM was *** aimed to simplify the TTM with a complex structure into a beam model with equal linear mass density,and the simulation results showed good *** dynamic equation was derived based on the equivalent model,and the effects of different factors on the vibration characteristics of the TTM were *** performance parameters were optimized based on a multiobjective genetic algorithm,and prototype production and load experiments were *** results show that the advantages of the new TTM can complete the deployment of large-scale solar sails,which is valuable for future deep space exploration.

关键词： Telescopic tubular mast Solar sail Genetic algorithm Modal analysis Optimization

The Structure and Formation Mechanism of a Sea Fog Event over the Yellow Sea

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Journal of Ocean University of China 2015年第1期14卷 27-37页

作者： GUO Jingtian LI pengyuan FU Gang z.ang Wei GAO Shanhong z.ang Suping Shandong Provincial Key Laboratory of Marine Ecology and Environment & Disaster Prevention and Mitigation North China Sea Marine Forecasting CenterState Oceanic Administration Laboratory of Physical Oceanography Department of Marine Meteorology Ocean University of China

In this paper, a heavy sea fog event occurring over the Yellow Sea on 11 April 2004 was investigated based upon observational and modeling analyses. From the observational analyses, this sea fog event is a typical advection cooling case. Sea surface temperature(SST) and specific humidity(SH) show strong gradients from south to north, in which warm water is located in the south and consequently, moisture is larger in the south than in the north due to evaporation processes. After fog formation, evaporation process provides more moisture into the air and further contributes to fog evolution. The sea fog event was reproduced by the Regional Atmospheric Modeling System(RAMS) reasonably. The roles of important physical processes such as radiation, turbulence as well as atmospheric stratification in sea fog's structure and its formation mechanisms were analyzed using the model results. The roles of long wave radiation cooling, turbulence as well as atmospheric stratification were analyzed based on the modeling results. It is found that the long wave radiative cooling at the fog top plays an important role in cooling down the fog layer through turbulence mixing. The fog top cooling can overpower warming from the surface. Sea fog develops upward with the aid of turbulence. The buoyancy term, i.e., the unstable layer, contributes to the generation of TKE in the fog region. However, the temperature inversion layer prevents fog from growing upward.

关键词： sea fog the Yellow Sea developing mechanism

An Analysis and Modeling Study of a Sea Fog Event over the Yellow and Bohai Seas

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Journal of Ocean University of China 2008年第1期7卷 27-34页

作者： FU Gang GUO Jingtian angeline Pendergrass LI pengyuan Laboratory of Physical Oceanography Department of Meteorology Ocean University of China Qingdao 266003 P. R. China Department of Meteorology University of-Miami Coral Gables FL 33146 USA

In this study, a sea fog event which occurred on 27 March 2005 over the Yellow and Bohai Seas was investigated observationally and numerically. Almost all available observational data were used, including satellite imagery of Geostationary Operational Environmental Satellite （GOES）-9, three data sets from station observations at Dandong, Dalian and Qingdao, objectively reanalyzed data of final run analysis （FNL） issued by the National Center for Environmental Prediction （NCEP） and Regional Atmospheric Modeling System （RANIS） results. Synoptic conditions and fog characteristics were analyzed. The fog formed when warm, moist air was advected northwards over the cool water of the Yellow and Bohai Seas, and dissipated when a cold front brought northerly winds and cool, dry air. In order to better understand the fog formation mechanism, a high-resolution RAMS modeling with a 6km×6km grid, initialized and validated by FNL data, was designed. A 48h modeling that started from 12 UTC 26 March 2005 reproduced the main characteristics of this sea fog event. The simulated lower visibility area agreed reasonably well with the sea fog region identified from the satellite imagery. Advection cooling effect seemed to play a significant role in the fog formation.

关键词： sea fog the Yellow and Bohai Seas satellite imagery numerical modeling low visibility area

Phenolic Profile, Antioxidant Activity and Anti-proliferative Activity of Crabapple Fruits

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Horticultural Plant Journal 2019年第4期5卷 155-163页

作者： Meiling Han Guo Li Xiaowei Liu Ai Li Peiqi Mao pengyuan Liu Houhua Li College of Landscape Architecture and Art Northwest A&F UniversityYanglingShaanxi712100China Faculty of Natural Sciences Institute of Horticultural Production SystemsFloricultureLeibniz University HannoverHannover D-30419Germany Novogene Bioinformatics Technology Co.Ltd Beijing100089China

To explore the potential of crabapples as functional food, polyphenols in crabapples and ‘Fuji’ apples were extracted, and the phenolic profile,total polyphenols, antioxidant activity and anti-proliferative activity against several human cancer cells were determined. The results indicated that crabapple extracts have more abundant phenols and higher total polyphenols(from 4.46 to 46.63 mg GAE·g-1 DW) compared to ‘Fuji’ *** extracts possessed higher antioxidant activity than apple by DPPH and ABTS analysis. All fruit extracts exhibited inhibitory effects on proliferation in different cancer cells;however, crabapple extracts performed significantly better, with half inhibitory concentration(IC50)values varied from 48.34 μg·m L-1 to 974.81 μg·m L-1 for colon cancer cells SW480, 64.67–1 466.35 μg·m L-1 for stomach cancer cells BGC-803,78.88–910.64 μg·m L-1 for esophageal cancer cells CaEs-17. Besides, the red crabapples had higher antioxidant activity and anti-proliferative activity than yellow fruits. These results showed that crabapples, especially red crabapples, have great potential as a healthy food, as they are rich in phenolic compounds with high antioxidant and anti-proliferative activities to cancer cells.

关键词： Crabapple Phenolic profile Antioxidant activity Anti-proliferative activity Human cancer cell

Molecular typing and resistance mechanisms of carbapenem resistantPseudomonas aeruginosa isolated from a Chinese surgical intensivecare unit

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Chinese Medical Journal 2014年第6期127卷 1071-1076页

作者： Meiying Yi pengyuan Wang Yucun Liu Department of Clinical Laboratory China-Japan Friendship Hospital Ministry of Health Beijing 100029 China. Department of General Surgery Peking University First Hospital Beijing 100034 China. Department of General Surgery Peking University First Hospital Beijing 100034 China. Email: yucunliu@***.

Background Carbapenems are an important class of drugs for the treatment of Pseudomonas aeruginosa(P. aeruginosa) infections. However, carbapenem resistance has been commonly observed in nonfermenter species of bacteria. The purpose of this study was to investigate the molecular epidemiology and carbapenem resistant mechanisms of P. aeruginosa isolated from a surgical intensive care unit(SICU) in China. Methods The molecular typing was analyzed by REP-PCR. Enzyme activity was measured with a 260 nm wavelength spectrophotometer. The levels of outer membrane proteins OprD and OprN were measured by Western blotting. The levels of mexA gene transcriptional expression were measured by quantitative real-time PCR. The metallo-beta-lactamase genes IMP, VIM, SPM, GES, and GIM were amplified by PCR. DNA fragments were sequenced by an automated ABI PRISM *** Forty-two strains resistant to carbapenems isolated from a SICU were analyzed. REP-PCR revealed 34 belonging to type A, a predominant strain in this SICU. But we did not find metallo-beta-lactamases IMP, VIM, SPM, GES, or GIM genes by PCR. With a three-dimensional extract test, we found 34 strains producing high levels of AmpC enzymes. We also observed the activity of beta-lactamases enzymes in the imipenem resistant group, which was statistically different from the sensitive group. Western blotting revealed that 23 strains showed loss of OprD, 18 strains had decreased OprD expression, and 14 strains expressed OprN. We discovered 27 strains that overexpressed mexA by quantitative real-time PCR, and the resistance rate to meropenem was statistically different between the overexpressing group and the lowexpressing group. Nucleotide sequences and deduced amino acid sequence analysis revealed that eight strains carried mutations in the mexR gene operon down regulating MexAB-OprM. The nucleotide sequences of mexR genes from PA36, PA41 and PA48 were submitted to the Genebank with accession numbers of AY899299, AY899300,

关键词： Pseudomonas aeruginosa fl-lactamase AmpC porin protein OprD elflux pump carbapenem resistance

A Kirchhoff-approximation numerical model for three-dimensional acoustic scattering from rough under-ice surfaces

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Chinese Journal of Acoustics 2021年第4期40卷 511-524页

作者： CHEN Wenjian LI Fubing YIN Jingwei zHOU Shunbo SUN Hui Lang pengyuan Acoustic Science and Technology Laboratory Harbin Engineering UniversityHarbin 150001 Key Laboratory of Marine Information Acquisition and Security(Harbin Engineering University) Ministry of Industry and Information TechnologyHarbin 150001 College of Underwater Acoustic Engineering Harbin Engineering UniversityHarbin 150001 School of Information and Communication Engineering Beijing Information Science and Technology UniversityBeijing 100101

A KirchhofF-approximation numerical method of three-dimensional acoustic scattering from a rough under-ice surface is *** triangulation is used to triangulate a Gaussian rough under-ice surface,the z-bufFer algorithm is used to remove the surface elements in the shadowed areas and obtain those in the bright areas,and the scattering intensity is calculated by the planar element method of Gordon's *** the numerical calculation model,the ice surface is regarded as one of local impedance,thereby incorporating it directly into the local reflection coefficient of the rough under-ice surface to calculate the scattering sound field and avoiding the approximation of the reflection coefficient in the analytical calculation *** scattering intensities of the numerical and analytical models are compared for under-ice surfaces with large and small roughness at different incident angles and *** the two types of results,those of the numerical calculation model are more consistent with measurements.

关键词： approximation numerical surfaces

Highly Efficient Blue Organic Light-Emitting Diode Based on a Pyrene[4,5-d]Imidazole-Pyrene Molecule

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CCS Chemistry 2022年第1期4卷 214-227页

作者： Yulong Liu Xiaxia Man Qing Bai Hui Liu pengyuan Liu Ying Fu Dehua Hu Ping Lu Yuguang Ma State Key Laboratory of Supramolecular Structure and Materials Department of ChemistryJilin UniversityChangchun 130012 Department of Chemistry College of Arts and SciencesNortheast Agricultural UniversityHarbin 150030 The First Hospital of Jilin University Changchun 130021 Institute of Polymer Optoelectronic Materials and Devices State Key Laboratory of Luminescent Materials and DevicesSouth China University of TechnologyGuangzhou 510640

Organic light-emitting diodes(OLEDs),which have been recently utilized in some flat-panel display screens such as mobile phones and televisions,show many merits,including light weight,high flexibility,energy preservation,and so forth,and are considered the next-generation displays and solid-state ***-emitting materials that can be applied in nondoped OLEDs with little efficiency roll-offs at high brightness are of great ***,a highly efficient,blue-emitting material,9-phenyl10-(4-(pyren-1-yl)phenyl)-9H-pyreno[4,5-d]imidazole(PyPI-Py),is achieved using pyrene[4,5-d]imidazole and pyrene as the weak electron donor and electron acceptor,*** nondoped blue OLED exhibits excellent performance with a maximum brightness of 75,687 cd m^(−2),a maximum current efficiency of 13.38 cd A−1,and a maximum external quantum efficiency(ηext)of 8.52%.Moreover,theηext is maintained at 8.35%and 8.05%at a brightness of 10,000 and 50,000 cd m^(−2),respectively,displaying extremely small efficiency roll-offs of 2.0%and 5.5%.The device characteristics are among the highest values for nondoped blue OLEDs and correspond to the best performance obtained for nondoped pyrene-based blue *** superior performance is attributed to the proper donor–acceptor design strategy which results in a quasi-equivalent hybrid local and charge-transfer excited state with the maximum generation of an 82%fraction of singlet excitons.

关键词： pyrene imidazole nondoped OLEDs blue emission efficiency roll-off

Exotic origin of the Chinese continental shelf: new insights into the tectonic evolution of the western Pacific and eastern China since the Mesozoic

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Science Bulletin 2015年第18期60卷 1598-1616页

作者： Yaoling Niu Yi Liu Qiqi Xue Fengli Shao Shuo Chen Meng Duan pengyuan Guo Hongmei Gong Yan Hu zhenxing Hu Juanjuan Kong Jiyong Li Jinju Liu Pu Sun Wenli Sun Lei Ye Yuanyuan Xiao Yu z.ang Institute of Oceanology Chinese Academy of Sciences Department of Earth Sciences Durham University School of Earth Science and Resources China University of Geosciences Institute of Deep Sea Science and Engineering Chinese Academy of Sciences School of Earth Sciences Lanzhou University

The effect of paleo-Pacific subduction on the geological evolution of the western Pacific and continental China is likely complex. Nevertheless, our analysis of the distribution of Mesozoic granitoids in the eastern continental China in space and time has led us to an interesting conclusion： The basement of the continental shelf beneath East and South China Seas may actually be of exotic origin geologically unrelated to the continental lithosphere of eastern China. By accepting the notion that the Jurassic- Cretaceous granitoids in the region are genetically associated with western Pacific subduction and the concept that subduction may cease to continue only if the trench is being jammed, then the termination of the granitoid magmatism throughout the vast region at -88±2 Ma manifests the likelihood of ＂sudden＂, or shortly beforehand （- 100 Ma）, trench jam of the Mesozoic western Pacific subduction. Trench jam happens if the incoming ＂plate＂ or portion of the plate contains a sizeable mass that is too buoyant to subduct. The best candidate for such a buoyant and unsubductable mass is either an oceanic plateau or a micro-continent. We hypothesize that the basement of the Chinese continental shelf represents such an exotic, buoyant and unsubductable mass, rather than seaward extension of the continental lithosphere of eastern China. The locus of the jammed trench （i.e., the suture） is predictably located on the shelf in the vicinity of, and parallel to, the arc-curved coastal line of the southeast continental China. It is not straightforward to locate the locus in the northern section of the East China Sea shelf because of the more recent （〈20 Ma） tectonic re-organization associated with the opening of the Sea of Japan. We predict that the trench jam at - 100 Ma led to the re-orientation of the Pacific plate motion in the course of NNW direction as inferred from the age-progressive Emperor Seamount Chain of Hawaiian hotspot origin （its oldest unsubdued Meiji and Detroi

关键词： Mesozoic granitoids in eastern ChinaExotic origin of Chinese continental shelf Trenchjam Transform plate boundary Basal hydrationweakening Lithosphere thinning Cratondestruction Mantle hydrous melting Crustalmelting Plate tectonics South China Sea

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风电机组状态监测系统节点路由修复算法

电力系统自动化 2015年第19期39卷 90-95页

作者：傅质馨丁国荣邵秋葵吕鹏远赵敏袁越河海大学能源与电气学院江苏省南京市211100 河海大学可再生能源发电技术教育部工程研究中心江苏省南京市210098 中国三峡新能源公司北京市100053 响水长江风力发电有限公司江苏省盐城市224000

为了解决风电机组状态监测系统因节点失效而产生的路由可靠性降低问题,提出了基于父节点及兄弟节点替代的节点路由修复算法。当监测数据在传输过程中遇到失效节点时,待传输数据的节点通过查询并获取自己的父节点和兄弟节点信息,优先利... 详细信息

为了解决风电机组状态监测系统因节点失效而产生的路由可靠性降低问题,提出了基于父节点及兄弟节点替代的节点路由修复算法。当监测数据在传输过程中遇到失效节点时,待传输数据的节点通过查询并获取自己的父节点和兄弟节点信息,优先利用其有效父节点进行路由替代,当且仅当该节点所有父节点均失效时才启用其兄弟节点进行路由替代,重新进行数据传输,达到提高监测系统路由可靠性的目的。通过仿真分析可知,基于父节点及兄弟节点替代的路由修复算法可显著提高风电机组状态监测系统的数据传输成功率。

关键词：风电机组状态监测系统无线传感器网络节点路由链路可靠性数据传输成功率