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RETURN PERIOD AND THE TREND OF EXTREME DISASTROUS RAINSTORM EVENTS IN ZHEJIANG PROVINCE

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Journal of Tropical Meteorology 2019年第2期25卷 192-200页

作者： chen hai-yan YU Hui YE Geng-jiao XU Ming yanG Qiu-zhen Zhejiang Provincial Meteorological Observatory Shanghai Typhoon Institute of CMA Guangxi Meteorological Service Center

A provincial Disaster-causing Rainstorm Severity Index(DRaSI) is introduced to quantify the relationship between rainfall and its disastrous impacts on Zhejiang province of China, shortened as ZJ-DRaSI. ZJ-DRaSI is set up based on the DRaSI for single stations in combination with the coverage of rainstorms. The probability distribution function(PDF) of ZJ-DRaSI between 1971 and 2015 can be well fitted by the Wakeby Distribution with five parameters. It is found that decadal(e.g. 10 yr, 20 yr, and so on) return period values of ZJ-DRaSI related to typhoons are generally lower than that of non-typhoon events, implying that disastrous non-typhoon events have a higher frequency of occurrence. The extreme typhoon events have a significant cycle of 22.5 years, while the non-typhoon events have a significant cycle of 15 years. Both are currently at the high-value phase. The annual extreme value of ZJ-DRaSI exhibits an increasing trend of approximately 15% every 10 years.

关键词： extreme disastrous rainstorm event probability distribution return period trend

分布式通信网络多频段信号源远程切换控制算法

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吉林大学学报（工学版） 2020年第5期50卷 1886-1893页

作者：陈海燕武汉理工大学信息工程学院武汉430070 北京电子科技职业学院电信工程学院北京102600

将传统多频段信号源切换控制算法应用在分布式通信网络当中无法实现稳定的信号源切换,为此提出多频段信号源远程切换控制算法。利用通信网络监控设备采样实时信号,并计算传输信号的所处频段。以通信信号的传输路径为基础实现对多频段信... 详细信息

将传统多频段信号源切换控制算法应用在分布式通信网络当中无法实现稳定的信号源切换,为此提出多频段信号源远程切换控制算法。利用通信网络监控设备采样实时信号,并计算传输信号的所处频段。以通信信号的传输路径为基础实现对多频段信号源的定位。安装远程控制设备并在其中设置切换控制的触发条件,最终通过切换接入点排序和电压与电流转换控制两个步骤,实现多频段信号源的远程切换控制。为验证远程切换控制算法的可行性,分别从控制抗阻塞性能和稳定性能两个方面实现测试,从而得出测试结论:远程切换控制算法比传统切换控制算法的抗阻塞性能提高了2.2%,且切换控制稳定性能更高。

关键词：分布式网络通信网络多频段信号源远程控制切换控制切换触发条件

Conformal Wavelet Finite-difference Time-domain Algorithm for Analysis of Milimeter Wave Attenuation on Coplanar Waveguide

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Semiconductor Photonics and Technology 2007年第3期13卷 206-209页

作者： DAI Hong-quan chen hai-yan School of Physics Science and Technology Yangtze University Jingzhou 434023 CHN

Addressed is the calculation of millimeter wave attenuation on coplanar waveguide(CPW). A novel conformal wavelet finite-difference time-domain(CWFDTD) algorithm is proposed with emphasis on its application in calculation of millimeter wave attenuation on CPW, which is the combination of conformal algorithm dealing with the deformed cell with Wavelet-FDTD using multi-resolution analysis(MRA). Derived is the difference formulation for multi-resolution time domain(MRTD) based on Daubechies wavelets, and also given is the stability conditions for wavelet-FDTD algorithm. To validate its accuracy and efficiency, this novel method is applied to calculate the millimeter wave attenuation on lithium niobate CPW. Numerical results demonstrate that this new CWFDTD algorithm has the same accuracy with the conformal finite-difference time-domain(CFDTD) and conformal finite-difference time-domain based on alternating-direction implicit method(ADI-CFDTD), but saves computational time and computer memory.

关键词： millimeter wave attenuation conformal wavelet FDTD algorithm multi-resolution analysis multi-resolution time domain coplanar waveguide

RAMAN SPECTRA OF LiYF_(4) CRYSTAL

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Chinese Physics Letters 1985年第9期2卷 421-424页

作者： GAN Fu-xi chen hai-yan Shanghai Institute of Optics and Fine Mechanics Academia SinicaShanghai

The polarized Raman spectra of lithium yttrium fluoride crystal for the incident light along different axes are presented and the vibrational modes of the crystal structure are discussed.

关键词： crystal vibrational fluoride

BFe10-1-1合金在NaCl溶液中点蚀行为的研究

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腐蚀科学与防护技术 2006年第4期18卷 289-291页

作者：陈海燕广东工业大学材料与能源学院广州510006

通过测定合金在不同pH值的0.5 mol/L NaCl溶液中的阳极极化曲线,以及用扫描电镜、原子吸收光谱对发生点蚀后的试样和溶液进行观察和成分分析,研究了铜镍合金BFe10-1-1在NaCl溶液中的腐蚀行为.结果表明:BFe10-1-1合金在酸性和弱碱性的0.5... 详细信息

通过测定合金在不同pH值的0.5 mol/L NaCl溶液中的阳极极化曲线,以及用扫描电镜、原子吸收光谱对发生点蚀后的试样和溶液进行观察和成分分析,研究了铜镍合金BFe10-1-1在NaCl溶液中的腐蚀行为.结果表明:BFe10-1-1合金在酸性和弱碱性的0.5 mol/L NaCl溶液下的腐蚀规律基本相似,在强碱性溶液中的低电位下,合金表面可以形成较稳定的钝化膜,因而耐蚀性能较好;当合金发生点腐蚀时,在点蚀坑内发生了脱镍腐蚀.

关键词：铜镍合金极化曲线点腐蚀脱镍腐蚀

Effects of Resonator Loss on Output Characteristics of Ring Microresonator Filter

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Semiconductor Photonics and Technology 2006年第4期12卷 257-261页

作者： HUANG Chun-xiong WU Pei-xuan chen hai-yan College of Physics Science and Technology Yangtzeu University Jingzhou 434023 CHN

The ring microresonator filter considering resonator inner loss is analyzed theoretically, which has one input port and two output ports. Some universal relations for coupling of optical power between microresonator and dielectric waveguides are presented. The analytical expressions of filter bandwidth or the full width at half maximum(FWHM), free spectral range and finesse of resonator are derived. The characteristics of the ring microresonator filter are discussed numerically. It is demonstrated that the loss of the ring resonator reduces the peak value of transmission, widens the filter bandwidth, and reduces the finesse of the resonator filter.

关键词： Optical filter Frequency filter Ring microresonator Optical channel filter Optical waveguide filters Finesse

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气流分级机操作参数对分级性能的影响

四川大学学报（工程科学版） 2006年第3期38卷 87-91页

作者：陈海焱陈文梅胥海伦四川大学化工学院四川成都610065 西南科技大学环境工程学院四川绵阳621010

在一定的假设条件下导出的气流分级机切割粒径公式,建立了切割粒径与操作参数(分级轮转速、流量和颗粒密度)的关系。在实际分级过程中,影响分级的因素很多,这些因素会造成分级机的分级实验值与切割粒径公式计算值不一致,甚至相反的结果... 详细信息

在一定的假设条件下导出的气流分级机切割粒径公式,建立了切割粒径与操作参数(分级轮转速、流量和颗粒密度)的关系。在实际分级过程中,影响分级的因素很多,这些因素会造成分级机的分级实验值与切割粒径公式计算值不一致,甚至相反的结果。利用自制的TCF-360叶片转子型离心式气流分级机,对其操作参数进行了系统的实验研究,得出了分级机操作参数与切割粒径和分级精度的相互关系,证明了分级机的转速、流量、二次风大小、分级区的气固浓度和进料粒度组成等操作参数均对分级机的性能有重要的影响。平衡改变分级机的流量与转速,切割粒径变化不大,分级精度和分级轮的磨损却随流量和转速的增加而增加。研究结果对分级机合理的操作参数的选取和结构设计具有一定的指导作用。

关键词：气流分级机气固浓度切割粒径

扫描参数校正模型在FY-3A红外分光计遥感图像定位校正中的应用

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红外与毫米波学报 2010年第4期29卷 293-296页

作者：陈海燕尹球胡勇中国科学院上海技术物理研究所上海200083 上海市卫星遥感和测量应用中心上海201100

研究了红外分光计(IRAS)图像定位结果存在偏差的总体规律,应用扫描参数校正模型定量地分析了扫描参数偏离对定位结果的影响,提出了修改扫描参数校正定位结果的参考方案.经校正后的定位结果与世界地理底图完全套合,验证了该方案的可行性.

关键词：红外分光计图像定位扫描参数

Verify UML Statecharts with SMV

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Wuhan University Journal of Natural Sciences 2001年第Z1期6卷 183-190页

作者： chen hai yan 1, Dong Wei 1, Wang Ji 1,2 , chen Huo wang 1 1 Department of Computer Science, National University of Defense Technology, Changsha 410073, China 2 State Key Laboratory for Software Engineering, Wuhan University, Wuhan 430072, C Department of Computer Science National University of Defense Technology Changsha China State Key Laboratory for Software Engineering Wuhan University Wuhan China

Formal verification has been widely needed in the development of safety critical systems. In order to introduce the design verification activity in UML developing process, we have developed a verifier of UML Statecharts by using the model checker SMV. The approach is to transform a system model in UML Statecharts to one in SMV input language via an intermediate language and then to verify the system properties specified in CTL by invoking SMV. The current experiences, including the formal verification of a simplified directory based cache coherence protocol in UML Statecharts, show that automatic verification can be integrated as a new step of the software process nicely.

关键词： formal verification UML statecharts EHA SMV