For understanding the damage and failure rule of rock under different uniaxial compressive loads and dynamic loads, tests on red sandstone were carried out on Instron 1342 electro-servo controlled testing system with ...For understanding the damage and failure rule of rock under different uniaxial compressive loads and dynamic loads, tests on red sandstone were carried out on Instron 1342 electro-servo controlled testing system with different uniaxial compressive loads of 0, 2, 4 and 6 MPa. It is found that peak stress, peak strain, elastic modulus and total strain energy decrease with the increase of static compressive stress. Based on the test results, the mechanism on damage and failure of rock was analyzed, and according to the equivalent strain hypothesis, a new constitutive model of elastic-plastic damage was established, and then the calculated results with the established model were compared with test results to show a good agreement. Furthermore the rule of releasing ratio of damage strain energy was discussed.展开更多
为了减少分簇式传感器网络中的数据传输量并均衡网络负载,提出了一种采用混合压缩感知(compressive sensing,CS)进行数据收集的方法.1)选取各临时簇中距离簇质心最近的一些节点为候选簇头节点,然后依据已确定的簇头节点到未确定的候选...为了减少分簇式传感器网络中的数据传输量并均衡网络负载,提出了一种采用混合压缩感知(compressive sensing,CS)进行数据收集的方法.1)选取各临时簇中距离簇质心最近的一些节点为候选簇头节点,然后依据已确定的簇头节点到未确定的候选簇头节点的距离依次确定簇头;2)各普通节点选择加入距离自己最近的簇中;3)贪婪构建一棵以Sink节点为根节点并连接所有簇头节点的数据传输树,对数据传输量高于门限值的节点使用CS压缩数据传输.仿真结果表明:当压缩比率为10时,数据传输量比Clustering without CS和SPT without CS分别减少了75%和65%,比SPT with Hybrid CS和Clustering with Hybrid CS分别减少了35%和20%;节点数据传输量标准差比Clustering without CS和SPT without CS分别减少了62%和81%,比SPT with Hybrid CS和Clustering with Hybrid CS分别减少了41%和19%.展开更多
文摘For understanding the damage and failure rule of rock under different uniaxial compressive loads and dynamic loads, tests on red sandstone were carried out on Instron 1342 electro-servo controlled testing system with different uniaxial compressive loads of 0, 2, 4 and 6 MPa. It is found that peak stress, peak strain, elastic modulus and total strain energy decrease with the increase of static compressive stress. Based on the test results, the mechanism on damage and failure of rock was analyzed, and according to the equivalent strain hypothesis, a new constitutive model of elastic-plastic damage was established, and then the calculated results with the established model were compared with test results to show a good agreement. Furthermore the rule of releasing ratio of damage strain energy was discussed.
文摘为了减少分簇式传感器网络中的数据传输量并均衡网络负载,提出了一种采用混合压缩感知(compressive sensing,CS)进行数据收集的方法.1)选取各临时簇中距离簇质心最近的一些节点为候选簇头节点,然后依据已确定的簇头节点到未确定的候选簇头节点的距离依次确定簇头;2)各普通节点选择加入距离自己最近的簇中;3)贪婪构建一棵以Sink节点为根节点并连接所有簇头节点的数据传输树,对数据传输量高于门限值的节点使用CS压缩数据传输.仿真结果表明:当压缩比率为10时,数据传输量比Clustering without CS和SPT without CS分别减少了75%和65%,比SPT with Hybrid CS和Clustering with Hybrid CS分别减少了35%和20%;节点数据传输量标准差比Clustering without CS和SPT without CS分别减少了62%和81%,比SPT with Hybrid CS和Clustering with Hybrid CS分别减少了41%和19%.
