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Estimating and Mapping Extreme Ice Accretion Hazard and Load Due to Freezing Rain at Canadian Sites

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International Journal of Disaster Risk Science 2023年第1期14卷 127-142页

作者： Chao sheng qian Tang H.P.Hong Department of Civil and Environmental Engineering University of Western OntarioLondonOntarioN6A 5B9Canada

The ice accretion load in Canadian structural design codes is developed based on an operational ice accretion prediction *** the present study,three models are employed to predict the ice accretion amount on a flat surface and horizontal wire at Canadian *** results confirm that the model used by Canadian practice for predicting ice accretion leads to a conservative estimate as compared to the remaining two *** results also indicate that the use of the Gumbel distribution for the annual maximum ice accretion is adequate for regions prone to ice accretion and that the lognormal distribution may be considered for regions with a moderate or negligible amount of ice *** of the ice accretion hazard at five selected Canadian sites are *** analysis of an equivalent wind speed that is concurrent with the iced wire is carried out,showing that the concurrent wind speed for the 50-year return period value of the annual maximum ice accretion amount is smaller than the 50-year return period value of the annual maximum wind *** is shown that the statistical characteristics of the annual maximum concurrent wind speed on iced wire differ from that of the annual maximum wind speed.

关键词： Canada Concurrent wind speed Hazard mapping Ice accretion Probabilistic analysis

Preface: Modern studies of variable stars

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Research in Astronomy and Astrophysics 2019年第3期19卷 1-2页

作者： Nikolay N.Samus sheng-Bang qian Institute of Astronomy Russian Academy of Sciences Yunnan Observatories Chinese Academy of Sciences

In this Mini-Volume, seven papers written on the basis of talks selected from those presented at the scientific conference "Modern studies of variable stars," commemorating Prof. M. A. Svechnikov(1933–2011), are published. The conference covered a variety of variable-star topics; the papers in this Mini-Volume deal with close, mainly eclipsing, binaries, Herbig Be stars and stellar molecular masers, with an accent on stellar catalogs of different kinds. We briefly review the contents of these papers.

关键词： stars variable-stars binaries-ISM general

Effect of Short Chain Alcohols upon Viscosity of TTAB Solution

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Chinese Journal of Chemical Physics 2008年第2期21卷 169-173页

作者： Yun-fei Yan Hua-zhen Li Hai-yang Yang Jia-sheng qian Ping-ping Zhu Ping-sheng He Department of Polymer Science and Engineering University of Science and Technology of China Hefei 230026 China

The effect of ethanol （C2H5OH）, propanol （C3H7OH）, and butanol （C4H9OH） upon the viscosity of tetradecyltrimethylammonium bromide （TTAB） solution in the presence or absence of KBr at 30℃was investigated, where the surfactant concentration CS is kept constant. In the absence of KBr, the relative viscosity ηr of TTAB solution increases linearly with the alcohol concentration CA, indicating that the alcohols do not promote micelle formation of TTAB. In the presence of KBr, ηr linearly decreases with CA for C2H5OH, but it exhibits a maximum with increasing CA for C3H7OH or C4H9OH. The facts reveal that C2H5OH or C4H9OH promotes the micelle formation of TTAB. A possible explanation is that the hydrophobicity of the mieellar interior is enhanced by KBr, so that C2H5OH or C4H9OH can dissolve in micelle and promotes micelle formation. In the presence of KCl, which is less efficient in promoting the micelle formation of cationic surfactant, both C3H7OH and C4H9OH have only a slight effect on the micelle formation. In contrast, due to the hydrophilicity, C2H5OH cannot dissolve in micelles in the presence of KBr or KCl.

关键词： Relative viscosity Cationic surfactant Organic additive Hydrophobic interaction

SDSS J012119.10 001949.9:a very short period M dwarf contact binary from SDSS stripe 82

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Research in Astronomy and Astrophysics 2015年第12期15卷 2237-2243页

作者： Lin-Qiao Jiang sheng-Bang qian Jia Zhang Yunnan Observatories Chinese Academy of Sciences Key Laboratory of the Structure and Evolution of Celestial Objects Chinese Academy of Sciences University of Chinese Academy of Sciences

We present the first multicolor photometric observations of the short period low-mass eclipsing binary SDSS J012119.10-4301949.9. By using the 2013 version of the Wilson-Devinney code, the photometric solutions are derived. It is found that the system is in a contact configuration （f = 18.9± 6.0%） with a moderate mass ratio of 0.5 ± 0.01. A third light contributing about 6.1± 1.3% of the total luminosity in the V band was found, which may come from a cool tertiary component. The derived high orbital inclination （i - 83.9°± 0.5°） and the almost symmetric three light curves suggest that the determined parameters are reliable. Both the color class and spectral class of the system correspond to a spectral type of M0, which may indicate that SDSS J012119.10-001949.9 belongs to a very rare class of M dwarf contact binaries that are below the theoretical short period limit.

关键词： binaries: eclipsing -- stars: individual (SDSS J012119.10-001949.9) --techniques: photometric

CORRESPONDENCE ANALYSIS ON IMAGES OF JIANGXI PROVINCE AS A TOURIST DESTINATION

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Chinese Geographical Science 2005年第3期15卷 275-280页

作者： MAO Duan-qian ZHANG Jie BAO Hao-sheng Department of Urban and Resources Sciences Nanjing University Nanjing 210093 P. R. China Department of Geography Jiangxi Normal University Nanchang 330027 P. R. China

This paper delineates the images of Jiangxi Province as tourist destination perceived by about 2000 sample visitors at Lushan Mountain and other 3 famous resorts (Jinggangshan Mountains, Longhushan Mountain, and Sanqingshan Mountain), with a result that the most common image is the famous scenic mountain image with partial attribute of image of religious culture destination. In order to reveal the similarities and dissimilarities of images among the four destinations, a correspondence analysis on 16 image attributes was employed. The results indicate that the tourists’ images on Longhushan Mountain, Sanqingshan Mountain and Lushan Mountain are very similar: having a lot of good tourist sites, famous mountain scenery, being close to nature and having good guide service, and others, but religious culture and good shopping facilities having not made deep impression on tourist, while Jinggangshan Mountains is famous for its red culture. The correspondence analysis visualizes the strengths and weaknesses of the destinations, which is useful for market positioning among the competitive places. Finally, some marketing suggestions for the four destinations were provided.

关键词： tourist destination image cognitive attribute evaluative attribute correspondence analysis

On properties of mass transfer in an Algol-type binary system:an example of VV Vir

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Research in Astronomy and Astrophysics 2014年第2期14卷 179-192页

作者： Jia Zhang sheng-Bang qian Lin-Qiao Jiang Yunnan Observatories Chinese Academy of Sciences Key Laboratory of the Structure and Evolution of Celestial Objects Chinese Academy of Sciences University of Chinese Academy of Sciences

Some properties of mass transfer within a semi-detached binary system are discussed based on an example of VV Vir. The observations and analysis of VV Vir show that it is a semi-detached binary system with the less massive cooler component filling its Roche lobe, which is also called an Algol-type binary system. Based on the parameters of this semi-detached binary, a theoretical study on the mass flow is carded out, including the trajectory of the mass flow, the position, radius and temperature of the impact spot caused by the mass flow, the inconsistent form of the mass flow and the possibly huge rate of energy transfer carried by the mass flow. Humps and distortions in light curves of VV Vir are deemed to be weak evidence for the theoretical results.

关键词： binaries eclipsing -- stars individual (VV Vir) -- techniques photo-metric

Candidates of eclipsing multiples based on extraneous eclipses on binary light curves： KIC 7622486, KIC 7668648, KIC 7670485 and KIC 8938628

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Research in Astronomy and Astrophysics 2017年第3期17卷 1-12页

作者： Jia Zhang sheng-Bang qian Jian-Duo He Yunnan Observatories Chinese Academy of Sciences Kunming 650216 China Key Laboratory of the Structure and Evolution of Celestial Objects Chinese Academy of Sciences Kunming 650216 China

Four candidates of eclipsing multiples, based on new extraneous eclipses found on Kepler binary light curves, are presented and studied. KIC 7622486 is a double eclipsing binary candidate with orbital periods of 2.2799960 d and 40.246503 d. The two binary systems do not eclipse each other in the line of sight, but there is mutual gravitational influence between them which leads to the small but definite eccentricity of 0.0035（0.0022） associated with the short 2.2799960 d period orbit. KIC 7668648 is a hierarchical quadruple system candidate, with two sets of solid 203 4- 5 d period extraneous eclipses and another independent set of extraneous eclipses. A clear and credible extraneous eclipse is found on the binary light curve of KIC 7670485 which makes it a triple system candidate. Two sets of extraneous eclipses with periods of about 390 d and 220 d are found on KIC 8938628 binary curves, which not only confirm the previous conclusion of the 388.5 4- 0.3 triple system, but also indicate new additional objects that make KIC 8938628 a hierarchical quadruple system candidate. The results from these four candidates will contribute to the field of eclipsing multiples.

关键词： binaries eclipsing - techniques photometric - methods observational

Asymptotic Property of Approximation to x~αsgn x by Newman Type Operators

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Acta Mathematicae Applicatae Sinica 2010年第4期26卷 617-624页

作者： qian Zhan Shu-sheng Xu Yue-hong Zhang Department of Mathematics Anhui University of Sciences and Technology Huainan 232001 China East China University of Sciences and Technology Shanghai 200237 China Yuanpei college Shaoxing University Shaoxing 312000 China

Approximation to the function ｜x｜ plays an important role in approximation theory. This paper studies the approximation to the function xαsgn x, which equals ｜x｜ if α = 1. We construct a Newman Type Operator rn... 详细信息

关键词： Rational approximation asymptotic property Newman type operator

Floating Clamping Mechanism of PT Fuel Injector and Its Dynamic Characteristics Analysis

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Chinese Journal of Mechanical Engineering 2012年第3期25卷 550-556页

作者： WANG Xinqing LIANG sheng XIA Tian WANG Dong qian Shuhua Engineering Institute of Engineering Corps University of Science&Technology of Chinese People's Liberation ArmyNanjing 210007China Bureau of Navy Engineering Design&Research Beijing 100841China

PT fuel injector is one of the most important parts of modern diesel *** satisfy the requirements of the rapid and accurate test of PT fuel injector,the self-adaptive floating clamping mechanism was developed and used in the relevant *** dynamic characteristics directly influence the test efficiency and ***,due to its special structure and complex oil pressure signal,related documents for evaluating dynamic characteristics of this mechanism are lack and some dynamic characteristics of this mechanism can＇t be extracted and recognized effectively by traditional *** at the problem above-mentioned,a new method based on Hilbert-Huang transform（HHT） is ***,combining with the actual working process,the dynamic liquid pressure signal of the mechanism is *** analyzing the pressure fluctuation during the whole working process in time domain,oil leakage and hydraulic shock in the clamping chamber are ***,owing to the nonlinearity and nonstationarity of pressure signal,empirical mode decomposition is used,and the signal is decomposed and reconstructed into forced vibration,free vibration and *** analyzing forced vibration in the time domain,machining error and installation error of cam are ***,free vibration component is analyzed in time-frequency domain with HHT,the traits of free vibration in the time-frequency domain are *** with traditional methods,Hilbert spectrum has higher time-frequency resolutions and higher *** improved mechanism based on the above analyses can guarantee the test accuracy of injector *** new method based on the analyses of the pressure signal and combined with HHT can provide scientific basis for evaluation,design improvement of the mechanism,and give references for dynamic characteristics analysis of the hydraulic system in the interrelated fields.

关键词： PT fuel injector floating clamping mechanism dynamic characteristics analysis Hilbert-Huang transform