风暴对滨海湿地潮沟水沙输运的影响——以长江口崇明东滩为例

为了探知风暴事件对滨海湿地潮沟水沙输运的影响,分别于平静天气和风暴天气("摩羯"和"温比亚"台风)条件下,在崇明东滩一典型潮沟进行了现场水沙数据观测。结果表明:台风期间近岸平均风速较平静天气增大3～4倍,有效波高增大7～15倍,盐沼前缘光滩和潮沟遭受强烈侵蚀,潮滩表层沉积物粗化1～2.1倍,水体悬沙浓度增大3～11倍,潮沟潮周期单宽泥沙输运通量增大4～33倍,单宽泥沙净输沙量增大8～17倍。风暴天气下,潮沟水沙输运呈现"大进大出"的特点,在盐沼潮滩内受盐沼植被消波、缓流和捕沙作用下,潮周期内单宽泥沙净通量指向盐沼潮滩,促进了盐沼滩内部泥沙的淤积。     

KP-90N电子数字求积仪分划值变形系数的测定方法

本文论述了KP-90N电子数字求积仪分划值变形系数的测定方法。从求积仪的脉冲变形,地形图的图纸变形两个方面进行综合考虑,最后导出了实用的分划值变形系数。并且指出了安置比例尺的计算方法。     

太阳微波脉冲事件中原区加热的证据

本对具有一定空间分辨率（￣４＇）和高灵敏度（０．００４ｓｆｕ）特性的１３．７ｍ射电望远镜，在１．３５ｃｍ（２２ＧＨｚ）波段上观测到的两个脉冲事件前的周期性脉动和吸收现象进行了分析，并认为这种观测特征，可用源区局部区域的加热得到合理解释。     

冰雹云雷达回波自动识别系统

利用CAPPI资料对立体风暴进行识别，计算并提供出实用的风暴结构参数，采用矩心踊跃法和矩不变量法相结合对单体风暴和混合性风暴回波进行跟踪；最小二第线性外推预报；根据WSD－88D的冰雹算法，在风暴结构基础上本文建立了Windows98操作平台上冰雹识别系统，经单站1年11次强对流天气过程的资料检验，结果表明：雹云识别精度达82％。系统建立了大量人机对话框以方便用户，增加实用性及推广性。     

Sequences in the Hardness Ratio-Peak Energy Plane of Gamma-Ray Bursts

The narrowness of the distribution of the peak energy of the vFv spectrum of gamma-ray bursts (GRBs) and the unification of GRB populations are great puzzles yet to be solved. We investigate the two puzzles based on the global spectral behaviors of different GRB populations, the long GRBs, the short GRBs, and the X-ray flashes (XRFs), in the HR - Ep plane (HR the spectral hardness ratio) with BATSE and HETE-2 observations. It is found that the long GRBs and the XRFs observed by HETE-2 seem to follow the same sequence in the HR-Ep plane, with the XRFs at the low end of this sequence. We fit the sequence by a universal Band function, and find that this sequence is mainly defined by the low energy index α, and is insensitive to the high energy index,β. With fixed β=-5, a best fit is given by α=-1.00 with X^2min/dof=2.2. The long and short GRBs observed by BATSE follow significantly different sequences in the HR-Ep plane, with most of the short GRBs having a larger hardness ratio than the long GRBs at a given Ep. For the long GRBs a best-fit yields α=-0.30 and β=-2.05. For the short GRBs, a best fit gives α=-0.60 with x^2min=1.1 (withβfixed at-2.0 because it is numerically unstable). The α value for the short GRBs is significantly greater than that for the long GRBs. These results indicate that the global spectral behaviors of the long GRB sample and the XRF sample are similar, while that of the short GRBs is different. The short GRBs seem to be a unique subclass of GRBs, and they are not the higher energy extension of the long GRBs.     

周末风暴（十）——亲历南极大救险

饮恨雷岛经历了昨晚长城海湾的风雪之夜,奥立格虽疲惫之极,却因出艇搜救未果而久不能眠。清晨7点51分,他突然接到韩国站呼叫,通报长城站在沙坝一带海岸发现遇险小艇物品,并请求加强对阿德雷岛一线继续搜寻。于是他分析了韩国人员在昨夜恶劣暴风雪中翻艇落水可能的过程,很快设想了自己下一步营救计划。8点30分,一辆改装的苏式装甲运兵车,装载着一支由俄罗斯队员为主的7人搜救队,急速向阿德雷     

Poisson-Logistic二元复合极值模型在平台甲板标高设计中的应用

考虑到平台所在海区台风出现的频次及其诱发之风、浪、潮、流极端海况联合出现的概率特性，本文推导出Poisson—Logistic二元复合极值模式，并以平台甲板标高进行实例计算。新模式增加了概率模型的物理内涵，解决了Logistic模型阈值选取的任意性。对海洋工程极端海况荷载组合预测具有广泛的应用前景。     

蓝绿激光探测水下目标的脉冲传输统计模拟及回波特性初步研究

文中给出了用蓝绿激光脉冲探测水下目标时的回波特性初步研究结果,所用的方法是对激光脉冲在海水中的传输作蒙特卡洛统计模拟.研究表明,位于目标上方空中的接收机收到的回波脉冲功率随着目标物水深的增加而呈指数下降,但随目标物反射的增加而增加.水体对激光的多次散射增强了回波脉冲功率,但也使脉冲明显变宽.