多路径网络编码的传输可靠性提高策略

为了提高无线传感器网络的传输可靠性,提出在中间节点选择性编码的多路径传输策略.该策略建立从源节点到汇聚节点的相交多路径,并在源节点对数据包进行编码后沿多路径传输,中间节点接收并转发编码包.如果中间节点是簇首节点,则需对数据包重新编码后再发送给下一跳节点.解析计算了路径的传输可靠性和标准化能耗,并对所提传输策略下的网络传输可靠性和能耗进行仿真.结果表明,所提策略使得网络的传输可靠性有所提高,而且能量有效性得到大幅改善.     

Genetic and molecular approaches to synthesis and action of the yeast killer toxin

Summary The K1 killer toxin ofSaccharomyces cerevisiae is a secreted, virally-coded protein lethal to sensitive yeasts. Killer yeasts are immune to the toxin they produce. This killer system has been extensively examined from genetic and molecular perspectives. Here we review the biology of killer yeasts, and examine the synthesis and action of the protein toxin and the immunity component. We summarise the structure of the toxin precursor gene and its protein products, outline the proteolytic processing of the toxin subunits from the precursor, and their passage through the yeast secretory pathway. We then discuss the mode of action of the toxin, its lectin-like interaction with a cell wall glucan, and its probable role in forming channels in the yeast plasma membrane. In addition we describe models of how a toxin precursor species functions as the immunity component, probably by interfering with channel formation. We conclude with a review of the functional domains of the toxin structural gene as determined by site-directed mutagenesis. This work has identified regions associated with glucan binding, toxin activity, and immunity.     

DCME中承载信道的动态指配过程及其优化

介绍了DCME(数字电路倍增设中关键技术之一的承载信道的动态分配方法,列举了承载业务的种类及相应的服务策略,提出了指配消息的优化方案及承载信道的限时刷新技术.     

环境渗透压影响硬骨鱼精子运动启动的研究进展

鱼类精子的运动启动受多种外界环境因素的影响,渗透压是影响大多数硬骨鱼类精子运动启动的重要因素.渗透压对鱼类精子运动启动的影响存在较大的种间差异和精子的个体差异,它通过影响精子细胞膜的形态结构、膜电位的变化和离子通道的开放状态,来调节鱼类精子运动启动的过程.     

Advanced continuous phase modulation for high mobility communications

This paper focuses on the design of continuous phase-modulated systems and simplified receiver for high- mobility wireless communications. A class of spectrally efficient coded modulation systems is proposed and ana- lyzed in terms of Euclidean distance and spectral effi- ciency. Moreover, the simplified detector based on mismatched receiver is designed to reduce the detection complexity exponentially for partial response systems. To deal with the fast time-varying channels without channel state information, a class of noncoherent detection algo- rithms for continuous phase modulation systems is devel- oped to offer near-coherent performance. The proposed system is assessed over both the additive white Gaussian noise and fast-fading channels. Numerical and simulated results show that the proposed system offers not only high spectral efficiency but also near-optimum performance over fast time-varying scenarios.     

论媒介融合背景下电视台台网互动的重要性

现今媒介发展的趋势无论是在西方发达国家还是在我国，或多或少、或深或浅的都出现了媒介“为了适应产业增长而发生的产业边界的模糊或消失”的现象，出现了媒介间的交叉、混合，甚至出现了多种媒介汇聚在一个传播平台上进行信息传播互动的情况。这种媒介间的互动是媒介融合背景下的必然趋势。     

含噪量子广播信道容量定理的求证与应用

量子广播信道是量子网络通信的基础。信道容量是信道最基本的特征,要利用信道进行有效可靠的通信,必须首先知道信道的容量。研究一个发送者、两个接收者的量子广播信道的容量问题。利用纠缠产生编码定理,求证了含噪量子广播信道容量定理,获得了含噪量子广播信道的经典-量子容量区域和量子-量子容量区域,并将该定理推广到量子去极化信道中,计算得到量子去极化广播信道的经典-量子容量区域。     

河南农产品营销渠道优化研究

在界定农产品营销渠道相关理论的基础上,阐述了农产品营销渠道的基本职能与类型,梳理了河南农产品营销渠道的现状及存在的问题,针对存在的问题进行优化分析,提出了优化对策。     

论地方政府民生政令的发布——以湖南衡阳“限摩”为例

地方政府的地方性政令往往容易宣传不到位、解释不清楚,极大地影响政令的实施效果。以湖南省衡阳市交通整治行动之一的＂限摩＂为例,此行动有利于国计民生,若要提高宣传深度、扩大宣传范围,以使其深入民心,可以提出很多具有可操作性的发布渠道,如数字电视、报纸、网络和广播等,更有运用数字电视机的开机语做广告、在银行驾校等公共场所发布传单等简单易行、成本低廉的手段。     

双选择性衰落信道下的频谱感知

为提高双选择性衰落信道环境下频谱感知性能,提出了一种基于改进的复指数基扩展模型进行信道建模的频谱检测方法.该方法是在一般的复指数基扩展模型的基础上,采用一种能自适应移动速度的基函数,在恒虚警概率条件下,利用接收信号的循环特征,对授权用户的频谱进行感知.实验结果表明,在低信噪比和认知用户移动速度不断变化的环境下该方法有较好的检测性能.