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Chinese Physics B 2019年第2期28卷 241-246页

作者： Li Jiang Ren-gang wan Department of Physics Changchun University of Science and Technology School of Physics and Information Technology Shaanxi Normal University

The absorption–dispersion properties of a microwave-driven five-level atom embedded in an isotropic photonic bandgap(PBG) have been studied. Due to the singular density of modes(DOM) in the isotropic PBG and the dynamically coherence induced by the coupling fields, modified reservoir-induced transparency and quantum interference-induced transparency emerge simultaneously. Their interaction leads to ultra-narrow spectral structure. As a result of closed-loop configuration, these features can be manipulated by the amplitudes and relative phase of the coherently driven fields. The position and width of PBG also have an influence on the spectra. The theoretical studies can provide us with more efficient methods to control the atomic absorption–dispersion properties, which have applications in optical switching and slow light.

关键词： isotropic photonic bandgap absorption–dispersion spectra phase and amplitude control ultranarrow spectral structure

Numerical simulation on the pressure wave in a 30 mm electrothermal-chemical gun with the discharge rod plasma generator

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Defence Technology（防务技术） 2019年第5期15卷 674-679页

作者： Yan-jie Ni Yong Jin gang wan Bao-ming Li National Key Laboratory of Transient Physics Nanjing University of Science and TechnologyNanjing 210094JiangsuChina China Academy of Ordnance 100089BeijingChina

An axisymmetric two-dimensional(2D)internal ballistic model including the transient burning rate law is used to simulate the 30mm electrothermal-chemical(ETC)launch with the discharge rod plasma generator(DRPG).The relationship between the pressure wave and the initial parameters,such as input electric power,discharging timing sequence,loading density and propellant web thickness,is researched through the change of initial parameters in the *** the condition of synchronous discharging,the maximum of the pressure wave can be controlled while the ratio of the input electric energy to the propellant chemical energy(electric energy ratio)is less than *** the electric energy ratio is larger than 0.11,the maximum of the pressure wave increases rapidly with the electric energy *** the increasing of the electric energy ratio,the change of the first negative amplitude value can be *** the condition of timing sequence discharging,the allowed input electric energy ratio to control the pressure wave is proportional to the current pulse *** the high electric energy ratio,the maximum of the pressure wave is inverse proportional to the current pulse *** pressure wave increases with the increasing of the loading *** the allowed electric energy ratio to control the pressure wave and the variation trend of the first negative amplitude wave value doesn't *** the discharging of the DRPG,the influence of changing propellant web thickness in ETC launch can be ignored.

关键词： Electrothermal-chemical launch Pressure wave Plasma Solid propellant Electric energy ratio

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多源遥感卫星影像区域网平差方法

测绘与空间地理信息 2025年第1期48卷 8-11页

作者：刘艳飞万刚张赛航天工程大学航天信息学院北京101416

多源遥感卫星影像对于灾害评估、耕地保护应用具有重要意义,为获得多源镶嵌正射影像,本文基于有理多项式成像模型,提出了一种多源遥感卫星影像区域网平差方法。在提出的方法中,对于给定的多源遥感卫星影像,首先计算特征点,然后根据特征... 详细信息

多源遥感卫星影像对于灾害评估、耕地保护应用具有重要意义,为获得多源镶嵌正射影像,本文基于有理多项式成像模型,提出了一种多源遥感卫星影像区域网平差方法。在提出的方法中,对于给定的多源遥感卫星影像,首先计算特征点,然后根据特征点提取结果,在各景影像之间进行同名点匹配,最后基于同名点根据最小二乘求解像方空间仿射变换参数。本文以天津市地区为实验区,采用资源三号和高分一号数据进行实验,实验结果表明本文提出的方法平面精度优于5 m,对于多源遥感影像应用分析具有重要作用。

关键词：多源遥感卫星影像正射影像有理多项式成像模型区域网平差

CLDASSD:Reconstructing Fine Textures of the Temperature Field Using Super-Resolution Technology

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Advances in Atmospheric Sciences 2022年第1期39卷 117-130页

作者： Ruian TIE Chunxiang SHI gang wan Xingjie HU Lihua KANG Lingling GE Institute of Aerospace Information Space Engineering UniversityBeijing 101400China National Meteorological Information Center China Meteorological AdministrationBeijing 100081China

Before 2008,the number of surface observation stations in China was ***,the surface observation data were too sparse to effectively support the High-resolution China Meteorological Administration’s Land Assimilation System(HRCLDAS)which ultimately inhibited the output of high-resolution and high-quality gridded *** paper proposes a statistical downscaling model based on a deep learning algorithm in super-resolution to research the above ***,we take temperature as an *** model is used to downscale the 0.0625°×0.0625°,2-m temperature data from the China Meteorological Administration’s Land Data Assimilation System(CLDAS)to 0.01°×0.01°,named *** performed quality control on the paired data from CLDAS and HRCLDAS,using data from 2018 and *** was trained on the data from 31 March 2018 to 28 February 2019,and then tested with the remaining ***,extensive experiments were conducted in the Beijing-Tianjin-Hebei region which features complex and diverse *** the HRCLDAS product and surface observation data as the"true values"and comparing them with the results of bilinear interpolation,especially in complex terrain such as mountains,the root mean square error(RMSE)of the CLDASSD output can be reduced by approximately 0.1℃,and its structural similarity(SSIM)was approximately 0.2 *** can estimate detailed textures,in terms of spatial distribution,with greater accuracy than bilinear interpolation and other sub-models and can perform the expected downscaling tasks.

关键词： statistical downscaling deep learning temperature field high-resolution reconstruction

Method of ballistic control and projectile rotation in a novel railgun

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Defence Technology（防务技术） 2018年第5期14卷 628-634页

作者： Bo Tang Ying-tao Xu gang wan Jiang Yue Yong Jin Hai-yuan Li National Key Laboratory of Transient Physics Nanjing University of Science and Technology

In order to realize the ballistic control of the railgun and the flight stability of the projectile, a new type of railgun is designed, which can control the muzzle velocity and rotation rate. The method of the muzzle velocity and overload control is to adjust the voltage or other parameters of pulse power supply. It would be easy to change velocity accurately in large wide. Another widespread concern problem is launching the spinning stability projectile by railgun. This paper designed a new structure of additional rails to generate an unsymmetrical magnetic field to produce rotational torque in armature. The structure is simple and can control the rotation rate by linear changing the barrel parameters. The calculation formulas of interior ballistic are derived by Biot-Safar law. The important parameter is the deflection angle of the additional rails relative to the symmetry plane of main rail. The larger the angle, the greater the rotation torque generated in the armature. To maintain the flight stability of the projectile, the barrel structural parameters should be proportional to the projectile structural parameters. When changing the muzzle velocity, the rotation rate will also be the equal proportion change. So that the gyro stability is the same. The experiment proves that the railgun designed in this paper can launch the projectile to rotate. And the rotational projectile may not cause the transition or much arcs. This method expands the application of the railgun.

关键词： Ballistic control Railgun Rotation Spin-stabilized projectile

Allelopathic effects of extracts from Solidago canadensis L. against seed germination and seedling growth of some plants

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Journal of Environmental Sciences 2006年第2期18卷 304-309页

作者： SUN Bing-yao TAN Jian-zhong wan Zhi-gang GU Fu-gen ZHU Ming-de College of Life Sciences Suzhou University Suzhou 215123 China School of Urbanology Suzhou University Suzhou 215123 China

To investigate the potential role of allelopathy in plant interference and in the successful invasion of alien species Solidago canadensis, aqueous and ethanolic extracts from rhizomes, stems and leaves of S. canadensis were prepared and used as treatment solutions to assess their effects on seed germination and seedling growth in four target species, mulberry （Morus alba）; morning glory （Pharbitis nil）, wheat （Triticum aestivum） and rape （Brassiea campestris）. Reduction and/or growth in germination and growth of the target plant species in the presence of both aqueous and ethanolic extracts at different concentrations indicated that the responses were species-specific and concentration-dependent. Generally, ethanolic extracts （especially from leaves） imposed stronger effects on both seed germination and seedling growth. Extracts with lower concentration at 0.001 g/ml dw could stimulate the seedling growth of rape and morning glory, whereas extracts at any given concentrations have inhibitory effects on wheat and mulberry. It is suggested that the aqueous and ethanolic extracts of all the three parts of S. canadensis have significant allelopathic effects. Although both inhibition and stimulation occurred in the germination and growth of the target species, extracts with higher concentrations definitely inhibit seed germination and seedling growth of all target plants. We suggest that allelopathy plays a more important role than other mechanisms do in the out-competition ofS. canadensis over other plants, and make it invasive in new habitats.

关键词： Canada goldenrod(Solidago cancutensis L.) allelopathy extracts seed germination seedling growth

Effect of drawing speedon properties of the antireflective SiO2 film based on glass

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Effect of drawing speedon properties of the antireflective S...

水电站钢闸门启闭机液压系统整体检修工艺浅析

第八届中国功能材料及其应用学术会议

作者： CANG Li-min JIANG Bing-jie YAN Tao wan Zhi-gang Henan Ancai High-Tech Co. LTD

ISBN: (纸本)9783037859698

The anti-reflective SiO film on glass was prepared by sol-gel process and dip-coating *** effect of drawing speed on properties of the SiOfilm was *** transmittance was tested by light spectrum transmittance testing system,the thickness and refractive index of SiO film was tested by spectroscopic *** increasing of the drawing speed from 100mm/min to 300 mm/min,the average of transmittance increment at first increased and then decreased,which reached the maximum4.24%at the speed 150mm/*** relations among transmittance,thickness(d) and refractive index(n) of the SiO film was dicussed.

关键词： SiO2 film sol-gel process anti-reflective transmittance drawing speed

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水电站机电技术 2025年第2期48卷 119-122,131页

作者：胡兴万刚朱思思连晓磊张波中国长江电力股份有限公司湖北宜昌443000 广州机械科学研究院有限公司广东广州510700

国内外水电站广泛采用液压启闭机作为各种类型闸门的专用起重机械装置,其具有运行平稳、传动效率高、结构布置简单、易于实现自动化等诸多优点。本文以某水电站机组快速门启闭机液压系统整体检修工艺为研究对象,总结了水电站钢闸门启闭... 详细信息

国内外水电站广泛采用液压启闭机作为各种类型闸门的专用起重机械装置,其具有运行平稳、传动效率高、结构布置简单、易于实现自动化等诸多优点。本文以某水电站机组快速门启闭机液压系统整体检修工艺为研究对象,总结了水电站钢闸门启闭机液压系统的工作原理,阐述了液压系统整体检修流程、质量控制标准和修后调试步骤,同时还提出了系统中集成阀组修后内泄漏试验模拟缸和实际缸的下滑量换算公式,为其他水电站闸门启闭机液压系统的整体检修工作提供经验参考。

关键词：液压启闭机液压系统整体检修

A longitudinal study of PSA and its influential factors in a cohort of Chinese men with initial PSA levels less than 4 ng ml-1

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Asian Journal of Andrology 2013年第4期15卷 483-486,I0007页

作者： Ming Liu Jian-Ye wang Hong-Xue Su gang wan Ling Zhu Xiao-Ming wang Beijing Hospital Department ot Urology Belling 100730 China

To evaluate the longitudinal change in prostate-specific antigen （PSA） and the influence of initial PSA on the PSA change. We retrospectively analysed health examination data collected at Beijing Hospital from March 2007 to November 2011. Men with an initial PSA levels less than 4 ng ml- 1 and an annual PSA test for 5 years were enrolled into the study. The men were separated into four groups by the initial PSA level （0-0.99, 1-1.99, 2-2.99 and 3-3.99 ng ml- 1）, and the difference in PSA change among the four groups was analysed. A total of 1330 men were enrolled into the study. The mean age, initial PSA and PSA velocity （PSAV） were 58.17± 14.63 （range 24-91） years, 1.18±0.79 （range 0-4） ng m1-1 and 0.04±0.25 （range -1.34±2.02） ng m1-1 year-1, Pearson＇s correlation analysis showed no correlation between initial PSA and PSAV （r=-0.036, P=0. 189）. The PSAV of the 0-0.99, 1-1.99, 2-2.99 and 3-3.99 ng m1-1 initial PSA groups was 0.03±0.11, 0.07±0.32, 0.03±0.34 and -0.01±0.43 ng m1-1 year-1, respectively （P=0.06）. As the initial PSA increased, the percentage of having a PSAV over 0.75 ng m1-1 year-1 and a negative PSAV both significantly increased. Males with a baseline PSA of 0-0.99, 1-1.99, 2-2.99 and 3-3.99 ng ml- 1 had a 1.88%, 6.16%, 16.30% and 57.81% chance, respectively, that their PSA would increase above 4.0 ng ml- 1 over the following 4 years （P〈0.0001）. The PSAV has no correlation with the initial PSA level. However, as the initial PSA increases, the chance that males will have an abnormal PSA or PSAV in the future increases.

关键词： male prostate cancer (PCa) prostate carcinoma tumour antigen prostate-specific antigen (PSA) PSA velocity

Creating a High-Quality S＆T Innovation Engine

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Qiu Shi 2018年第3期10卷 94-100页

作者： wan gang Vice Chairman of the 13th National Committee of the Chinese People's Political Consultative Conference President of the China Association for Science and Technology and former Minister of Science and Technology of the People's Republic of China