双模场真空态与相干态的叠加态及其部分非经典性质

构造了辐射场的一类新的非经典态,即双模真空态与相干态的叠加态.并讨论了它的非经典性质,即压缩效应、亚泊松分布、两模间二阶相关函数.数值计算结果表明,双模真空态与相干态的叠加态具有非常显著的非经典性质,因此双模真空态与相干态的叠加态是一类新的非经典光场态.     

一种改进的冗余规则修剪方法

在修剪冗余规则已有算法的基础上,引入相关性这一概念,提出了一种改进的冗余规则修剪方法.实验结果证明该算法能够有效地减少关联规则的数量.     

塔里木盆地塔东2井寒武系稠油分子化石与油源分析

综合运用同位素质谱、色谱、色谱-质谱技术手段研究了塔东2井寒武系稠油分子化石特征。结果表明，塔东2井寒武系稠油具高伽马蜡烷、高C28甾烷、低重排甾烷和高C27-三芳甾烷的特征，与寒武系-下奥陶统烃源岩的分子化石特征类似，说明塔东2井寒武系原油源自寒武系-下奥陶烃源岩；塔东2井稠油中检出高丰度的稠环化合物（荧蒽、芘、苯并[a]蒽、屈、苯并荧蒽、苯并芘），全油的碳同位素值明显偏重，揭示了原油烃类经热蚀变发生稠化。     

南亚边缘海域热带气旋年频次与对流层风场变化的关系

利用1958—1998年NCAR/NCEP再分析资料和美国海军联合台风警报中心JTWC(Joint Typhoon Warning Center)提供的同时期南亚边缘海域(包括阿拉伯海、孟加拉湾和南海)热带气旋资料,分析了这3个海域热带风暴高发期气候上100hPa和850hPa风矢量特征,以及100hPa纬向风强度分别与这3个海域热带气旋年频次之间的关系。结果表明:在阿拉伯海及孟加拉湾热带气旋生成数与100hPa东风气流强度之间存在极好的正相关关系,即东风气流加强热带气旋数目增多,反之减少。而南海由于位于南亚高压东南侧,经向风的显著地位使南海热带气旋与100hPa经向风强弱变化有联系而与纬向风的关系减弱。     

Major factors controllin8 the formation of middle and large marine carbonate stratigraphic fields

Marine carbonate oil and gas fields have become an important exploration area in China and even across the world. Their formation, distribution and enrichment are special owing to the complexity of the deposition, diagenesis and accumulation, which is caused by the multiplicity of the carbonate de- positional environments and facies, huge extensions of formation time and burial depth, complication of diagenetic evolution, heterogeneity as well as the development of pores, caves and fractures affected by various factors. Oil and gas accumulations in carbonate rocks are not strictly controlled by the second-order structure belt. Most of them, under certain structural settings, are controlled by sedimentary diagenesis and its favorable facies. The hydrocarbon reservoir type is predominantly stratigraphic. Based on the worldwide researches of carbonate fields, the paper concludes that 7 main factors control the formation and distribution of middle-large marine carbonate stratigraphic fields.     

突然开孔对平屋盖结构静动力风荷载的影响

采用刚性模型和气动弹性模型风洞试验,研究迎风面突然开孔对平屋盖结构静动力风荷载的影响.根据试验结果,分析了开孔前后平屋盖结构的平均风压系数、均方根风压系数和风振响应的变化规律,提出了开孔结构平屋盖净风压的计算方法,以及平屋盖风振系数的简化处理方法.研究表明:迎风面突然开孔会大幅增大平屋盖结构的静动力风荷载,在结构设计中必须考虑内外压的联合作用及相应的风致动力效应,但静动力风荷载的比值变化不大,因此仍可沿用封闭结构的风振系数.     

A comprehensive review concerning the problem of marine crudes sources in Tarim Basin

The issue of source of oil/gas in the platform basin area in Tarim Basin has been debated for a long time, and the debate is focused on whether the marine oil/gas resources that have been discovered in the basin were originated from hydrocarbon source rocks in the Cambrian-Lower Ordovician or in the Mid-Upper Ordovician. In this paper a summary was made in regard to the major points and supporting data by the predecessors, and a discussion was conducted toward the core issues related to the study on the oil source in the Tarim Basin area, such as choice of correlation parameters, influence of maturation and physical differentiation on oil source correlation parameters, and geological and geochemical significance of these relevant correlation indices. It is quite probable that different interpretation results could arise from the oil source correlation due to choice of parameters severely affected by the thermal maturation and physical differentiation effect, and insisted that only those parameters that come with clearly defined geochemical significance and are less affected by thermal maturation and variations occurring during secondary evolution process are valid ones. The marine crude in Tarim Basin covers contributions that were originated from two sets of hydrocarbon source rocks as mentioned above but dominated by the one from the Mid-Upper Ordovician hydrocarbon source rocks. Here oil of mixed sources occurs extensively, and crude from Cambrian sources was also discovered. It is suggested that for further study on the origin of marine crudes in Tarim Basin, the parameters used for correlation of oil sources shall be optimized, and a comprehensive set of geological and geochemical methods shall be adopted for this purpose.     

关联维数在旋转机械支承系统状态监测中的应用

提出用关联维数来定量描述旋转机械支承系统的工作状态，进而对系统进行故障诊断，文中首先采用迭代奇异值降噪算法对转子支承系统不同状态下的信号进行降噪处理，然后计算子信号的关联维数，分析结果表明，系统不同运行状况对应的关联维数明显不同，因此可以用关联维数作为支承系统工作状态的特征参数，并能提供设备故障诊断的准确率。     

状态空间模型方程阶次的辨识

为了判定状态空间方程的阶次 ,提出了相关分析方法。其步骤是 :把状态空间模型化为能观测性规范性 ,导出系统输出相关函数所满足的线性回归方程 ,通过观查数据乘积矩矩阵行列式随其维数的变化情况 ,从而确定系统的阶次。该方法的特点是 :无论系统是否存在噪声 ,都是通过检验某一准则函数值是否为零而获得系统阶次。在系统无噪声和有噪声两种情况下进行了数字仿真研究 ,利用相关方法确定的阶次与系统的真实阶次相吻合。结果表明 :该文的方法在判定状态空间方程的阶次方面是有效的     

用于图像信息隐藏检测的位平面相关分析法

从理论上研究了信息隐藏对空域数据统计特性的影响，利用位平面分割技术，分析了原图为伪图各位平面数据的统计特性。在此基础上，定义了一种位平面相关密度函数和相关几率分布图，提出了针对空域隐藏法的位平面分割相关分析法。