提高电缆电视系统图像信号传输质量的技术措施

从电缆电视系统中各频道信号的幅度均衡角度出发，指出了指高电缆电视系统中图像信号传输质量的几种技术措施，并对系统中干线放大器增益和电缆线的合理选择与图像传输质量的关系进行了探讨。     

关于两线偏振光波叠加问题的讨论

通过对同频率、任意振动方向、相位差恒定的两列线偏振光波叠加问题的讨论，得到相干条件、椭圆偏振的一般表述     

干涉膜厚度的研究

对普通单色光源照射下干涉膜厚度超过一定限度不产生干涉现象的原因作了多方面分析，并从实验和理论两方面给出了能产生干涉现象的膜厚度的量值。     

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.     

Measurement of creep of optical fiber by a low coherent white light double interferometer system

The creep properties of optical fiber used in fiber optical sensors were studied in this paper.A low coherent white light double interferometer system was designed and calibrated and the creep deformations of optical fibers under static and cyclic loadings were measured with this device.The research results showed that polymer coated optical fibers crept at the beginning when they were under static or cyclic load.As the number of the cyclic loading or the static loading times increased the creep tended to s...     

二能级开放量子系统相干保持的最优控制策略

二能级量子系统在开放环境下的相干保持是量子器件实用化的关键.针对二能级开放量子系统的相干保持问题,首先将系统的主方程模型转化为实向量空间上的状态空间模型.然后借助经典最优控制的思想,提出了一种既保证系统控制能量最小,同时又最大程度的减小消相干的最优控制策略.最后就一个典型的二能级开放量子系统仿真实现其相干保持,仿真结果显示了该方案的优越性.     

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.     

二能级原子Dressed态的非经典特性

通过精确求解二能级原子与场相互作用时的哈密顿量的本征值,得到了自发辐射下的二能级原子的Dressed态.加入基态后,用完备集来描述原子和场组成的系统.经过计算后,得到了场方差一般表达式及场的二阶相干度,并求得初始条件下的压缩最佳值.     

指数函数与动态电路的研究

从电路分析的角度，将电路信号归结为4类，研究了指数信号的特性及冲激信号产生的电路结构特点；当电路有冲激电输入且换路定则不成立时，给出了确定初始值的假设表达式．     

未知相关噪声下的广义波达方向估计算法

针对未知相关噪声情况下信源波达方向的估计,提出一种适用于均匀线阵的广义波达方向估计算法。该算法利用修正后的协方差差分算法,有效地消除了阵元间的相关噪声的影响。不同于以前的算法,提出的算法通过对接收数据的前后向空间平滑协方差矩阵进行共轭运算得到新的变换矩阵,因此修正后的协方差差分矩阵是个实部为零的厄米特矩阵,从而有效地降低了特征分解过程的计算量。本算法能解决相关噪声下,同时分辨相干与非相干信源的问题。理论分析和仿真结果均表明所提算法的有效性。