针对Quasi-UDG模型下无线传感器网络随机部署的拓扑特征,提出了一种非测距基于权重的定位算法EWLS(Enhanced Weighted Least Square).首先,设计出一种节点跳数和距离关系估计的方法,然后依据跳数值与距离关系的概率表达式,给出EWLS定位...针对Quasi-UDG模型下无线传感器网络随机部署的拓扑特征,提出了一种非测距基于权重的定位算法EWLS(Enhanced Weighted Least Square).首先,设计出一种节点跳数和距离关系估计的方法,然后依据跳数值与距离关系的概率表达式,给出EWLS定位算法中节点测量距离信息的权重.仿真实验表明,在不同的锚节点密度、Quasi-UDG模型因子和平均邻居节点数的参数下,EWLS算法定位误差较小,同最小均方误差相比,有效地提高了节点定位的精度.展开更多
一、什么是BIM?1999年,美国科幻电影《黑客帝国》横空出世,其异常前卫的世界观设定,即使放到今天来看也未过时,随着人类科技水平的日新月异,虚拟现实[1]逐渐呈现于人们的视野之中。作为建筑行业的虚拟现实技术,BIM的概念首先于1975年,...一、什么是BIM?1999年,美国科幻电影《黑客帝国》横空出世,其异常前卫的世界观设定,即使放到今天来看也未过时,随着人类科技水平的日新月异,虚拟现实[1]逐渐呈现于人们的视野之中。作为建筑行业的虚拟现实技术,BIM的概念首先于1975年,由美国乔治亚理工大学Charles Eastman教授提出,其全称为"Building Information Modeling",在中国被称为"建筑信息模型"。简单来说,BIM是指某将建工程在现场动工以前,与该工程相关的所有人员,包括业主。展开更多
A model of the universe (preprint 2019), based on a quantum approach to the evolution of space-time as well as on an equation of state that retains all the infinitesimal terms, has made it possible to estimate a large...A model of the universe (preprint 2019), based on a quantum approach to the evolution of space-time as well as on an equation of state that retains all the infinitesimal terms, has made it possible to estimate a large number of parameters relating to the universe and in particular the estimation of a colossal phantom energy E<sub>Λ</sub> represented by the existence of a hidden photon ŷpresent everywhere. This energy undergoes dilution in H<sup>4</sup> due to expansion of the universe. In order to introduce the effects of this energy on the curvature of space-time, we chose to express it by the cosmological constant Λ in the equation of the GR via the element tensor T<sup>00</sup>. This positive energy E<sub>Λ</sub> which acts as additional effect to gravity and we have expressed this energy in the form of an equation which expresses a so-called cosmological force F<sub>Λ</sub>. We estimated that this photon or hidden particle of spin 1 has an energy ~1 [meV] at our cosmic position t<sub>0</sub> which makes it an ultra-light axion ULA. Subsequently, with the action of this augmented force, especially in the first 400 [My] we were able to explain, in part, the rapid development of galaxy formation as seen by JWST as well as several observed dynamic behaviors of the barionic mass of some galaxies as MW, M33, UGC12591, NGC3198, UGC2885 and NGC253 whose observations raise questions and require additional explanations that led to the likely existence of unobserved matter called DM. However, it appears that this cosmological force makes it possible to explain several observations without the use of this DM. A first conclusion was drawn, namely the much earlier formation of galaxies by the action of this cosmological force coupled with gravity (GLASS z12). In addition, the model made it possible to explain the need or not to use the concept of DM for ETGs and LTGs by the more or less early and long period of the beginning of galaxy formation over a period ranging from ~170 to 1200 [My]. Thus, the model makes it possible to explain to a large extent the observations of the dynamics of the galaxies studied. However, several questions remain.展开更多
提出了一种适用于无线Ad Hoc网络的路由算法GLFCFR(G reedy and Local F in ite C lose FaceRouting),该算法以RNG(Relative Ne ighborhood G raph)图作为无线网络的拓扑结构,利用节点中存储的邻节点位置信息和网络局部有限闭平面上的...提出了一种适用于无线Ad Hoc网络的路由算法GLFCFR(G reedy and Local F in ite C lose FaceRouting),该算法以RNG(Relative Ne ighborhood G raph)图作为无线网络的拓扑结构,利用节点中存储的邻节点位置信息和网络局部有限闭平面上的节点位置信息实现了数据分组的转发.随着网络中节点数的增加以及节点移动性的增强,该路由算法具有良好的可扩展性和适应性,通过仿真可看出GLFCFR算法在路由分组开销和数据分组的成功传输率方面具有良好的性能.展开更多
文摘针对Quasi-UDG模型下无线传感器网络随机部署的拓扑特征,提出了一种非测距基于权重的定位算法EWLS(Enhanced Weighted Least Square).首先,设计出一种节点跳数和距离关系估计的方法,然后依据跳数值与距离关系的概率表达式,给出EWLS定位算法中节点测量距离信息的权重.仿真实验表明,在不同的锚节点密度、Quasi-UDG模型因子和平均邻居节点数的参数下,EWLS算法定位误差较小,同最小均方误差相比,有效地提高了节点定位的精度.
文摘一、什么是BIM?1999年,美国科幻电影《黑客帝国》横空出世,其异常前卫的世界观设定,即使放到今天来看也未过时,随着人类科技水平的日新月异,虚拟现实[1]逐渐呈现于人们的视野之中。作为建筑行业的虚拟现实技术,BIM的概念首先于1975年,由美国乔治亚理工大学Charles Eastman教授提出,其全称为"Building Information Modeling",在中国被称为"建筑信息模型"。简单来说,BIM是指某将建工程在现场动工以前,与该工程相关的所有人员,包括业主。
文摘A model of the universe (preprint 2019), based on a quantum approach to the evolution of space-time as well as on an equation of state that retains all the infinitesimal terms, has made it possible to estimate a large number of parameters relating to the universe and in particular the estimation of a colossal phantom energy E<sub>Λ</sub> represented by the existence of a hidden photon ŷpresent everywhere. This energy undergoes dilution in H<sup>4</sup> due to expansion of the universe. In order to introduce the effects of this energy on the curvature of space-time, we chose to express it by the cosmological constant Λ in the equation of the GR via the element tensor T<sup>00</sup>. This positive energy E<sub>Λ</sub> which acts as additional effect to gravity and we have expressed this energy in the form of an equation which expresses a so-called cosmological force F<sub>Λ</sub>. We estimated that this photon or hidden particle of spin 1 has an energy ~1 [meV] at our cosmic position t<sub>0</sub> which makes it an ultra-light axion ULA. Subsequently, with the action of this augmented force, especially in the first 400 [My] we were able to explain, in part, the rapid development of galaxy formation as seen by JWST as well as several observed dynamic behaviors of the barionic mass of some galaxies as MW, M33, UGC12591, NGC3198, UGC2885 and NGC253 whose observations raise questions and require additional explanations that led to the likely existence of unobserved matter called DM. However, it appears that this cosmological force makes it possible to explain several observations without the use of this DM. A first conclusion was drawn, namely the much earlier formation of galaxies by the action of this cosmological force coupled with gravity (GLASS z12). In addition, the model made it possible to explain the need or not to use the concept of DM for ETGs and LTGs by the more or less early and long period of the beginning of galaxy formation over a period ranging from ~170 to 1200 [My]. Thus, the model makes it possible to explain to a large extent the observations of the dynamics of the galaxies studied. However, several questions remain.
文摘提出了一种适用于无线Ad Hoc网络的路由算法GLFCFR(G reedy and Local F in ite C lose FaceRouting),该算法以RNG(Relative Ne ighborhood G raph)图作为无线网络的拓扑结构,利用节点中存储的邻节点位置信息和网络局部有限闭平面上的节点位置信息实现了数据分组的转发.随着网络中节点数的增加以及节点移动性的增强,该路由算法具有良好的可扩展性和适应性,通过仿真可看出GLFCFR算法在路由分组开销和数据分组的成功传输率方面具有良好的性能.
