网络时代大学出版社保持学术传播主导地位研究

面对信息化和网络化的冲击，伴随着学术传播方式的变化，大学出版社在学术传播中的作用也在发生相应的改变，而且面临着挑战与机遇。为此，大学出版社应充分利用网络化优势，加强自身信息化建设；以网络为平台，提高自身的学术影响力；注意加强与数字图书馆的协调与合作，通过设计一个对彼此都有利的合作基础，共同促进学术的传播与发展。     

Information-sharing in social networks

We present a new model for reasoning about the way information is shared among friends in a social network and the resulting ways in which the social network fragments. Our model formalizes the intuition that revealing personal information in social settings involves a trade-off between the benefits of sharing information with friends, and the risks that additional gossiping will propagate it to someone with whom one is not on friendly terms but who is within oneʼs community. We study the behavior of rational agents in such a situation, and we characterize the existence and computability of stable information-sharing configurations, in which agents do not have an incentive to change the set of partners with whom they share information. We analyze the implications of these stable configurations for social welfare and the resulting fragmentation of the social network.     

基于PID和PWM技术的直流电机控制

阐述了单片机通过PID和PWM技术实现对角度传感器的控制过程和编程要点．给出了系统的组成框图,分析了单片机实现PWM控制技术的设计方法和PID算法原理．并给出了由PWM信号驱动直流电机的一般设计方法。     

多孔介质反应器中甲烷预混气体燃烧火焰传播特性研究

分别以氧化铝小球(5mm和8mm)和氧化铝泡沫陶瓷(孔密度为10PPI和40PPI)为多孔介质,对甲烷与空气预混气体火焰传播特性进行实验,研究了多孔介质结构和入口预混气体流速对火焰的影响。研究表明,火焰可以稳定在多孔介质前半段,多孔介质反应器中温度分布均匀。大直径的氧化铝小球燃烧速率更快。燃烧波波速随入口空气流量的增大而增大。泡沫陶瓷反应器火焰很快传播到反应器上游,再慢慢预热升温;氧化铝小球反应器则燃烧温度达到到峰值后,再缓慢向反应器上游传播。     

民航微博传播模式及影响因素研究

微博已经成为很多企业进行信息沟通和品牌传播的重要渠道。很多企业通过这一新型平台宣传企业自身,取得了良好的效果。本文基于微博概念、信息论与社交网络理论等相关理论描绘出航空运输企业官方微博的传播路径,总结民航微博传播模式,提出影响民航微博传播的因素。     

一种用于SCMA系统的混合期望传播检测方法

作为一种新的非正交多址接入技术,稀疏码多址接入（Sparse Code Multiple Access,SCMA）被提出以支持大规模连接。基于稀疏因子图,SCMA利用低复杂度的消息传递算法（Message Passing Algorithm,MPA）来实现接近最优的多用户检测。但是,传统MPA的复杂度仍然很高。为了灵活地控制算法的复杂性,提出了一种混合期望传播检测算法用于SCMA检测,建立算法复杂度与信道阈值之间的关系,利用信道阈值控制算法复杂度。此外,将混合期望传播检测算法与消息回退机制相结合以提高性能。仿真结果表明,与其他检测方案相比,所提算法可以灵活地在算法性能和计算复杂度之间进行折衷。     

双曲正弦高斯脉冲传输过程中三阶色散的影响

利用计算机数值模拟法,研究了有无啁啾两种双曲正弦高斯脉冲在光纤中传输时,三阶色散单独作用及二、三阶色散共同作用时对其的影响,模拟结果表明：啁啾参数C和群速度色散参数β之2间的关系将会严重影响双曲正弦高斯脉冲的传输效果。     

Characterization of delay propagation in the air traffic network

We build a delay propagation network based on Bayesian Network approach to study the complex phenomenon of delay propagation within a large network consisting of the 100 busiest airports in the United States. Through topological analysis and probability analysis, we investigate the characterization of delay propagation among airports and the impact of different types of airports on delay propagation. Results indicate that the cumulative degree distribution of the delay propagation network follows an exponential function and flight delays take at most one transhipment to go from each airport to any other airports on average. For each individual airport, the effects of delay propagation are associated with airports size (traffic flow), small airports are easily affected by other airports while large airports are more affecting downstream airports but fewer affected by upstream airports. Finally, we show how the number of affected airports changes as a function of the delayed airports based on different simulation strategies.     

基于现场总线的面粉脉冲式压运瞰分布式控制系统

通过一个例子介绍了一种基于现场总线的面粉脉冲式压运系统的原理和控制方法．采用现场总线技术和智能模块的控制系统,不仅实现自动控制,而且增加了负荷和诊断功能,实践表明,该系统低成本、可靠性高、易于维护,操作方便。给企业带来显著效益。     

试论湖北旅游形象的定位与塑造

在分析湖北旅游现状和对湖北现有旅游形象定位评析的基础上,根据湖北的地脉、文脉和商脉,将湖北的旅游形象重新定位为＂神奇江山.浪漫楚风＂,并提出了湖北旅游形象塑造与建设的思路。