J/ψ衰变到重子、反重子对中SU(3)对称性破坏的研究

利用粒子数据手册(PDG2004)公布的J/ψ衰变到重子、反重子对(BB)各个衰变道分支比的平均值, 对重子八重态的SU(3)对称性重新做了分析. 研究了J/ψ→BB中电磁相互作用和强相互作用的干涉. 得到了在J/ψ→BB中SU(3)单态、电磁 相互作用和SU(3)破坏各个因素所占的大小.     

Prisoner＇s Dilemma Game with Nonlinear Attractive Effect on Regular Small-World Networks

We investigate a spatial Prisoner＇s Dilemma game with nonlinear attractive effect on regular small-world networks. The players located on the sites of networks can either cooperate with their neighbours or defect. In every generation, each player updates its strategy by firstly choosing one of the neighbours with a probability proportional to .A^α denoting the attractiveness of the neighbour, where .4 is the collected payoff and ^α （-〉0） is a free parameter characterizing the extent of nonlinear effect. Then each player adopts its strategy with a probability dependent on their payoff difference. Using Monte Carlo simulations, we investigate the density pc of cooperators in the stationary state for various values of α and the rewiring probability q of the network. It is shown that the introduction of such attractive effect remarkably promotes the emergence and persistence of cooperation over a wide range of the temptation to defect for the same network structures. We also point out that long-range connections either enhance or inhibit the cooperation, which depends on the value of α and the payoff parameter b.     

居民收入和消费预测的灰理论方法

阐述灰色模型GM(1,1)建立及检验的基本理论和方法.并依据2000年—2005年浙江农村居民人均纯收入和人均生活消费数据,利用GM(1,1)模型建模方法,对“十一五”期间浙江农民的纯收入和生活消费进行了预测.     

���������������������͵�������

??In this paper, by applying the moment inequality for asymptotically almost negatively associated (AANA, in short) random sequence and truncated method, the equivalent conditions of complete moment convergence of the maximum partial for weighted sums of AANA random variables are obtained without assumptions of identical distribution, which generalize and improve the corresponding ones of{15},{16} and {17}, respectively.     

X波段介质和金属膜片混合加载行波加速结构的传播特性计算及模型腔的有关研究

计算了X波段(f=9.37GHz)介质和金属膜片混合加载行波加速结构的TM₀₁模和HEM₁₁模的色散曲线, 结果表明HEM₁₁模的截止频率比TM₀₁模的低, 说明与盘荷波导相比, 该种新加速结构单束团的BBU效应得到改善.实验研究优选得到了适用于该种新加速结构的介质(ε_r=5.812). 采用MAFIA程序优化设计了模型腔, 测试频率与设计的数值吻合得很好.     

线性递归序列模q

设{u_k}_k≥0为一个线性递归序列．序列{u_k(mod q)}_(k≥0)是周期的,很多人都对其周期有过研究．本文应用二次数域中理想的理论,较完全地刻面了二次线性递归序列模q的周期长度,所获结果加强并推广了Engstrom及Wall的结论．     

超声波提取-等离子体原子发射光谱测定何首乌中的磷脂

采用超声波提取法提取中药何首乌中磷脂类化合物,探讨了提取溶剂用量、提取时间及超声功率等因素对磷脂提取率的影响,结合ICP-AES分析法对提取的磷脂类化合物进行了测定.结果表明,对于1.5 g何首乌,用20 mL Folch试剂,超声提取35 min,超声功率为24 kHz的条件下磷脂提取率较高.     

多媒体教育资源库层次索引模型

依据多媒体教育资源各层次特征及其关系,通过定义资源媒体特征空间,构建了教育资源库层次索引模型,各层次特征间的映射规则将资源的高层语义特征映射到低层媒体特征,达到了扩充描述语义的目的,提高了查全率;结合学科本体,规范了资源标注内容和用户查询条件的描述,减少了人为因素对查询项和索引项匹配相似度计算的影响,提高了查准率.     

轴流式水轮机三维非定常湍流计算及压力脉动预测

水轮机的稳定性研究是目前工程上大型水轮机组流动分析的重要课题,本文以某水电站的大型轴流转桨式水轮机原型为基础建立计算模型,完成了从蜗壳进口到尾水管出口整个流道的非定常湍流计算,预测了固定导叶进口、转轮后、尾水管进口等多个位置的压力脉动,并利用FFT变换进行分析得到了压力脉动的频率和幅值,探讨了水轮机全流道内压力脉动产生和传播的原理．