大型设备监测用新型无线传感器网络

针对工业环境大型设备的状态监测,对无线传感器网络节点及网络结构进行优化.将网络节点分为3个级别,并分别进行能耗及功能设计,综合提高网络生命周期.分析了大型设备周边无线信道特征,针对小尺度衰落及设备运转时对信号的随机遮挡,提出一种多簇头协作式超簇结构的无线传感器网络.仿真结果表明,超簇结构无线传感器网络的网络连通度及网络生存期明显优于传统无线传感器网络.     

右半直线上依分布收敛独立随机环境中随机游动的吸收概率

主要讨论右半直线上独立随机环境中带有吸收壁的随机游动,在假定环境满足一定条件下证明了一个强大数定律,并应用该定律 计算了其吸收概率。     

论旅游地的旅游环境质量评价

世界旅游业迅速发展的事实已经说明,旅游与环境的关系极为密切的微妙。尤其对于旅游接待地来讲,处于强势的旅游开发经营活动与处于弱势的环境相互作用,旅游开发经营对环境的负面影响,以及环境对旅游持续发展的制约,均已十分明显。因此,为促进旅游业的可持续发展,提高旅游业的经济效益、社会效益及环境效益,重要对策之一是大力优化旅游环境质量,其中,对旅游环境质量进行评价是旅游建设和保护的重要基础。     

随机环境中的独立过程

引进遍历性条件,利用分析方法研究了随机环境中独立随机过程,重点讨论马氏环境中的0－1分布、Posson分布和一般离散分布,得到了这些分布的数学期望、方差,证明了它们均满足大数定理。     

清代皖西引种玉米甘薯史实及其检讨

明中叶后,美洲的玉米与甘薯越过大洋,先后来到中国安家落户,也走进皖西淮河、长江支流的一处处谷地和上游大别山区的高山腹地。玉米和甘薯是比较典型的旱粮作物,它们不太苛刻的种植条件带来了两种作物的极度扩张,从而为中国人的食物结构加进了新元素,从根本上改变了种植地民众食物不足的困境,尤其是解决了山区越冬食物不足和春荒的困难。但何炳棣整体史学的思维告诉我们,玉米和甘薯的引种,也带来了人口的激增;涌向山地的农民由于缺乏山地耕作的经验,又造成了水土流失和环境危急的日益严重。当然,只要能采取波伦式谨慎选择的态度,玉米和甘薯基本上是个好东西。历史的启示是,人类与自然之间只能走一条共同进化的路。     

Model of Markov Chains in Space-Time Random Environments

A general framework of stochastic model for a Markov chain in a space-time random environment is introduced, here the environment ξ^＊：={ξ1,x∈N,x∈ X}is a random field. We study the dependence relations between the environment and the original chain, especially the ＂feedback＂. Some equivalence theorems and law of large numbers are obtained.     

Climate change transformation: A definition and typology to guide decision making in urban environments

Climate change presents a threat to the sustainability of cities and their societies, and must be adequately addressed. Urban environments (cities) are responsible for the creation of a significant amount of greenhouse gas emissions which are the source of climate change. Cities have been increasingly the focus of action to address climate change, yet emissions are not significantly reducing. Additionally, there a lack of integration between adaptation and mitigation. This prevents responses adequate to limit global warming to 1.5^OC, and to be well adapted to anticipated changes. This paper critically analyses existing definitions and typologies of climate change actions. A definition of ‘climate change transformation’ is proposed which includes the integration of adaptation and mitigation goals to enable a new regime in which global warming is limited to 1.5^OC. A new three-part typology: ‘coping, malaction and transformation,’ is presented for categorising climate change actions by the extent to which they integrate adaptation and mitigation, and define a new regime. The typology is accompanied by illustrations to demonstrate the relationship between adaptation and mitigation. The definition, typology and illustration serve to guide effective climate change decision making, and provides principles to guide application in urban environments.     

随机环境中马氏链的状态研究

利用马氏链的一般理论和Foguel的L1理论,讨论了随机环境中马氏链状态的性质,得到了状态强常返存在的充分条件、状态正则本质与强常返的关系,以及在一定条件下保守集与其任意非空子集的关系．     

古城正定旅游环境质量的数学评价模式

旅游环境质量与旅游可持续发展之间存在极为密切的关系，实现可持续发展的关键就是旅游环境质量问题。这里以历史文化名城正定为研究区域，在实地调查和与专家座谈的基础上设计问卷，通过定量和定性分析，构建旅游环境质量数学评价模型，对古城正定旅游区的旅游环境质量做出了评判。