Mating behaviour and maternal care in the tropical savanna funnel-web spider Aglaoctenus lagotis Holmberg (Araneae: Lycosidae)

Despite their abundance and diversity, Neotropical spiders have been the subject of relatively few studies of behavioural ecology. The sexual behaviour and maternal care of the spider Aglaoctenus lagotis (Lycosidae) is described here. We performed experimental manipulations to test the hypothesis that males are attracted by female cues in the web. Two predictions were tested: (a) webs used by a virgin female will attract more males than webs used by an inseminated female; (b) the main cue in the web is chemical, so webs recently used by virgin females will attract more males than those that are not recently used. Additionally, we tested the hypothesis that maternal care increases offspring survivorship. Results showed that males are attracted by recently used webs (z = 0.0015; p = 0.037; z-test) and webs of virgin females (z = 0.041; p = 0.036, z-test). Male sexual behaviour presented three different categories: court, pre-mate and mate. After the mating, the females built a cocoon that was transported adhered to the spinnerets and held by the last pair of legs. After the hatching of the eggs, the young migrated to the dorsal region of the mother's body for 5 days. During maternal care the mother eliminates a yellowish drop from its oral cavity, which is collected by the young. During the development of the young until adulthood, the offspring that have their mother present in the first stages of life have greater survival compared with those without maternal care. Our results make it possible to perform comparative analyses between a South American Lycosidae species and other species distributed worldwide.     

跳频同步信号的干扰仿真研究

跳频信号的同步过程是跳频通信系统的关键.一旦同步信号被干扰,整个跳频系统将无法正常工作.在分析了跳频同步信号侦收的可行性及目前干扰跳频同步信号方法的局限性的基础上,提出了一种新的干扰方法--部分驻留时间干扰,并将干信驻留时间比作为影响跳频同步信号的又一重要指标.仿真结果表明该干扰方法可在较小干扰功率下有效干扰跳频同步信号.     

Web日志挖掘中重构网站结构技术

提出了一种重构网站结构的方法,并将此方法应用于Web日志挖掘的数据预处理中．实验表明,本方法能够更好地还原用户访问情景,为Web日志挖掘提供有效数据。     

线性步进频率编码信号特性的研究

通过理论分析和实际计算,对线性步进频率编码信号(LSDFC)的模糊图、多普勒灵敏性和分辨力等特性进行了研究。结果表明这种信号易于产生和处理,适合用于要求大时宽大带宽的场合。     

福建行洛坑钨矿变异函数模型的研究

以行洛坑细-网脉状钨矿为实例,对服从对数正态分布的区域化变量,分别用原始品位值和对数变换值建立变异函数模型。通过交叉验证等方法研究表明,对原始数据进行对数变换所得到的模型能更好地揭示区域化变量的空间变化规律,而且,对数线性克立格估值也比线性克立格估值更佳。     

高TcRF—SQUID测量人体磁场

新研制成功的、工作于液氮温度下的高临界转变温度超导量子干涉器(以下简写成为高Tc RF—SQUID),加上磁聚焦器之后,测量磁场的灵敏度已达10~(-12)T(10~(-(?)G).在国家地震局的零磁实验室中,我们用这样的RF—SQUID,初步地测得了与心脏跳动及手指动脉血流有关的人体磁信号.     

测井资料的自动分层和岩性识别

介绍了用测井资料进行相分析中的自动分层和岩性识别技术。采用的分层方法为最优分割法,岩性识别用统计分类中的贝叶斯判别法则。通过实际资料的处理解释,取得了与钻井地质剖面吻合良好的结果。     

Robust序贯检测及窄带随机相位信号的Robust M-检测

Robust检测是信号检测的一个新分支,不仅可用于已知信号的检测,还可用于随机信号与随机参量信号的检测等方面.本文首先讨论将序贯检测方式引入有限样本的Robust检测,导出Robust序贯概率比检测器RSPRT,证明其具有提高信号处理速度和节约平均样本等优点.本文还针对雷达和声纳系统常遇到的窄带随机相位信号,研究如何利用位置参数M-估计方法和理论,导出了窄带随机相位信号的Robust M-检测器,经过计算机模拟证明具有良好的Robust性.     

信号极点估计的状态空间方法

研究了基于状态空间模型的阻尼指数和信号参数的估计方法，建立了阻尼指数和信号的状态空间状态空间模型，并进行了计算机模拟，该方法以奇异值分解和特征分解为基础，无需对高次方程求根，可以直接从系统状态传输矩阵得到信号的极点，结果表明，计算量小，具有较好的估计性能。     

矿井轨道运输信、集、闭系统模拟

编制了井下运输信、集、闭系统计算饥模拟模型ＴＲＡＮ—２．提出了信号区间设置的原则和方法．根据某大型矿井的实际生产系统．确定了最佳的信号区间长度及信号点个数．并给出了矿井不同发展阶段系统的能力及相应的信号设置．对产量、线路通过能力及信号位置作了大量方案的动态分析。