赤潮信息系统综合分析应用

对赤潮遥感信息及同步采集的赤潮优势种类的光谱数据与同步采集的生物、化学、水文、气象等相关观测数据作了分析,在VisualFoxpro集成系统环境下,研究了地物光谱数据处理算法,以及利用地物光谱数据提取赤潮优势种类等生物信息的方法,并阐述了赤潮生物优势种类识别和赤潮生物特征量分析的应用及赤潮生物的监测。     

天气雷达探测遭电子干扰分析与解决途径

随着电子技术的不断发展,各种无线发射装置的广泛应用,无线接收设备尤其是高灵敏度的雷达都有可能遭遇各种意想不到的电子干扰.通过分析经历过的多起雷达受扰事件,挑选包括气象部门雷达相互间的同频干扰,与军用雷达相互间的同频干扰,微波接力站和民用超高频数传机对天气雷达的干扰等几起具有代表性的典型个例,就其发生现象、检判过程、产生的原因、实际解决办法和最终结果以及带来的相关启示做了一些分析探讨,可为从事技术保障的同行提供有益的借鉴.     

FY-4A/AGRI传感器波段平均太阳辐照度计算及不确定性分析

传感器大气顶层波段平均太阳辐照度(Band-Averaged Extraterrestrial Solar Irradiance,BAESI)是表观反射率和星上辐亮度之间转换的重要因子,为了针对FY-4A/AGRI有关通道较为准确地计算这一数值,分别以韩国COMS/GOCI、美国GEOS-16/ABI、日本Himawari-8/9/AHI传感器为例,利用国际上常用的6条太阳光谱曲线与传感器光谱响应函数参与计算BAESI,并与各传感器BAESI标准值进行比较。结果表明,Kurucz计算结果平均绝对误差与均方根误差均最小,是最理想的太阳光谱曲线,此外,Kurucz计算值与各传感器各波段BAESI标准值的最大偏差均小于4.5%,最大偏差百分比及对应波段分别为-2.39%(GOCI-band3)、1.49%(ABI-band6)、4.28%(AHI-08-band6)、4.42%(AHI-09-band6)。因此选择Kurucz太阳光谱曲线参与计算FY-4A/AGRI传感器各波段BAESI值,给出相应结果,并分析了计算值的不确定性,解决了将表观反射率转换为辐射亮度的困难。     

1964-2013年大连地区暴雨气候特征及变化规律

利用1964—2013年大连地区6个气象站逐日降水资料,采用线性倾向估计、Mann-Kendall和 Yamamoto检验及最大熵谱分析等方法,对大连地区暴雨的气候特征及变化规律进行分析。结果表明：大连地区3—12月均可出现暴雨,72.7％的暴雨出现在7—8月,7月暴雨出现最多,8月上旬是暴雨出现最集中的时期。4—8月各月暴雨日数均呈上升趋势,且4月暴雨日数上升最明显,8月次之,至9月暴雨日数呈下降趋势。大连地区各站年平均暴雨日数为1.8—2.8 d,暴雨日数分布从大连西北内陆向东南沿海地区逐渐增多,暴雨日数大值中心在庄河（2.8 d）。各站年暴雨日数均呈上升趋势,大连北部普兰店、东部长海和西南部旅顺地区年暴雨日数呈显著上升趋势,其他地区年暴雨日数上升趋势较弱。近50 a来,大连地区暴雨初日有所提前,暴雨终日变化不明显。年暴雨日数、暴雨强度和暴雨贡献率均呈不显著的上升趋势,且均从2003年以来增加明显,均有2.0—3.0 a的周期振荡;此外,年暴雨日数、暴雨强度和暴雨贡献率分别存在准12.5 a、准5.0 a和准16.7 a的振荡周期,仅年暴雨贡献率在1977年和1978年发生显著突变。     

The focus parameters and their correlation from small earthquakes before and after the 1995 Douhe earthquake

IntroductionTheseismoIogymethodofearthquakepredictionissometimessimplycalled"predictingearthquakebyearthquake",thatis,animpendinglargeearthquakeispredictedonbasisofsomefeaturesofsmaIlearthquakesoccurredbeforeit.Forthispurpose,thecharactersoftemporaryspatiaIandmagnitudedistributionofsmalIearthquakesareintensiveIyinvestigated,whichareusuallycalIedasseismicitymethod.ThesuccessfuIpredictionofHaichengearthquakeinl975wasitSremarkabIeappIication.Besides,thepossibIechangesincharactersofseismicsou…     

钢筋混凝土框架结构直接基于位移的抗震设计

直接基于位移的抗震设计方法是对基于力的抗震设计方法的重大改进。按此方法进行设计时,需要解决的关键问题是确定结构的目标位移和相应的侧移模式。提出用框架梁节点截面屈服时的位移作为目标位移,并推导了层间屈服位移的计算公式;然后用结构近似的第一振型曲线作勾其侧移模式,对层间屈服位移进行修正。算例表明,本方法计算结果合理。     

云南地震数字遥测台网子台地动噪声分析

介绍了云南数字遥测台网的基本情况，阐述了地动噪声有效值和功率谱的计算方法。对选取的资料进行预处理后，计算分析了云南数字遥测台网全部子台的地动噪声水平，按地动噪声水平对子台进行了分类。指出了地动噪声分析对台网建设的作用。     

Estimating the confidence of earthquake damage scenarios: examples from a logic tree approach

Earthquake loss estimation is now becoming an important tool in mitigation planning, where the loss modeling usually is based on a parameterized mathematical representation of the damage problem. In parallel with the development and improvement of such models, the question of sensitivity to parameters that carry uncertainties becomes increasingly important. We have to this end applied the capacity spectrum method (CSM) as described in FEMA HAZUS-MH. Multi-hazard Loss Estimation Methodology, Earthquake Model, Advanced Engineering Building Module. Federal Emergency Management Agency, United States (2003), and investigated the effects of selected parameters. The results demonstrate that loss scenarios may easily vary by as much as a factor of two because of simple parameter variations. Of particular importance for the uncertainty is the construction quality of the structure. These results represent a warning against simple acceptance of unbounded damage scenarios and strongly support the development of computational methods in which parameter uncertainties are propagated through the computations to facilitate confidence bounds for the damage scenarios.     

Analytical model for fully three‐dimensional radial dispersion in a finite‐thickness aquifer

Analytical solutions for contaminant transport in a non‐uniform flow filed are very difficult and relatively rare in subsurface hydrology. The difficulty is because of the fact that velocity vector in the non‐uniform flow field is space‐dependent rather than constant. In this study, an analytical model is presented for describing the three‐dimensional contaminant transport from an area source in a radial flow field which is a simplest case of the non‐uniform flow. The development of the analytical model is achieved by coupling the power series technique, the Laplace transform and the two finite Fourier cosine transform. The developed analytical model is examined by comparing with the Laplace transform finite difference (LTFD) solution. Excellent agreements between the developed analytical model and the numerical model certificate the accuracy of the developed model. The developed model can evaluate solution for Peclet number up to 100. Moreover, the mathematical behaviours of the developed solution are also studied. More specifically, a hypothetical convergent flow tracer test is considered as an illustrative example to demonstrate the three‐dimensional concentration distribution in a radial flow field. The developed model can serve as benchmark to check the more comprehensive three‐dimensional numerical solutions describing non‐uniform flow contaminant transport. Copyright © 2009 John Wiley & Sons, Ltd.