The conventional deadline and budget constrained (DBC) scheduling heuristics for economic-based computational grids does not take the inconsistency of grid heterogeneity into account, which can lead to decline of ap...The conventional deadline and budget constrained (DBC) scheduling heuristics for economic-based computational grids does not take the inconsistency of grid heterogeneity into account, which can lead to decline of application completion ratios. Motivated by this fact, a novel DI3C scheduling heuristics was proposed to deal with sequential workflow applications. In order to valuate the inconsistency, the relative cost (RC) metric was introduced, which was used to indicate the task-starving degree for resources. The new algorithm assigns tasks to resources, considering completion time, budget and RC together. The GridSim toolkit and the benchmark suites of the standard performance evaluation corporation (SPEC) were used to simulate the heterogeneous grid environment and applications. The experimental results show that the task and workflow completion ratios of the new heuristics are higher than those of the conventional heuristics.展开更多
In China,the primary energy bases and the energyrequirement areas are mismatched,which presents theremote and reverse distribution characteristics,and thelarge-scale power flow is from the west to the cast andfrom the...In China,the primary energy bases and the energyrequirement areas are mismatched,which presents theremote and reverse distribution characteristics,and thelarge-scale power flow is from the west to the cast andfrom the north to the south.In this paper,according tothe above characteristics and the power flow pattern,thelarge-scale,high-efficiency and long-distance UHVACand UHVDC combined transmission scheme is investi-gated and proposed,and the development mode ofChina's power grid and the planning scheme of‘NorthChina-Central China-East China'synchronous UHV gridwhich can satisfy the healthy and sustainabledevelopment of China's economy and society is proposedand optimized.展开更多
为了有效集成基于主体的模型(Agent Based Model,ABM)和地理信息系统(Geographical Information System,GIS),将经典地理信息系统的功能从着重宏观地理格局的描述扩展到注重微观行为机制的刻画,作者提出并设计了一个具备网格计算能力的...为了有效集成基于主体的模型(Agent Based Model,ABM)和地理信息系统(Geographical Information System,GIS),将经典地理信息系统的功能从着重宏观地理格局的描述扩展到注重微观行为机制的刻画,作者提出并设计了一个具备网格计算能力的集成化城市微模拟平台---Grid ABGIS。首先回顾了目前城市微模拟研究进展,通过对城市微模拟系统信息过程进行归纳和总结,从软件工程的角度提出了"七步法"城市模拟信息工程的基本框架;其次分析了通用多主体城市模拟软件平台Grid ABGIS的信息处理流程和相应的系统需求;最后对Grid ABGIS的系统结构、对象体系结构、数据模型和城市主体对象模板进行了详细设计,进而实现了一个ABGIS原型系统。展开更多
针对无线传感器网络占空比MAC协议在链路或节点失效环境下易导致严重的能量浪费问题,提出了一种基于Grid Quorum的异步低占空比M AC协议-AGQ-M AC(Asynchronous Grid Quorum M AC).AGQ-M AC采用Grid Quorum组分配信道,通过动态调配Quoru...针对无线传感器网络占空比MAC协议在链路或节点失效环境下易导致严重的能量浪费问题,提出了一种基于Grid Quorum的异步低占空比M AC协议-AGQ-M AC(Asynchronous Grid Quorum M AC).AGQ-M AC采用Grid Quorum组分配信道,通过动态调配Quorum比率得到了节点的最优占空比,并在邻节点发现过程中采用双前导序文抽样来监测信道状态,以减少节点唤醒时间从而达到能量高效.仿真实验结果表明,与其他占空比MAC协议相比,AGQ-MAC延长了网络生存时间,降低了网络能耗,提高了邻发现数据传输率,同时保持较低的平均邻发现延迟.展开更多
针对格网DEM难以对黄土高原梯田地形进行有效数字表达的问题,基于面向对象思想提出了能够顾及梯田地形的Grid-TIN混合格网DEM(Grid-TIN based DEM,GT-DEM)概念及其数据模型,并阐明其主要特征及与传统DEM的关系。以陕西绥德县辛店沟小流...针对格网DEM难以对黄土高原梯田地形进行有效数字表达的问题,基于面向对象思想提出了能够顾及梯田地形的Grid-TIN混合格网DEM(Grid-TIN based DEM,GT-DEM)概念及其数据模型,并阐明其主要特征及与传统DEM的关系。以陕西绥德县辛店沟小流域水平梯田为例,利用现有1∶1万格网DEM、梯田特征点线及其外围边界线,构建出能够充分顾及梯田地形的GT-DEM。研究表明,利用现有格网DEM和梯田地形特征点线构建顾及梯田地形GT-DEM的技术可行。GT-DEM不仅可对研究区全局地形进行粗略表达,而且可对其局部梯田地形进行精细表达。该研究是对如何提高DEM的梯田地形数字表达能力的有益探索,对进一步提高DEM对淤地坝、鱼鳞坑等其他人工地形的数字表达能力具有重要借鉴意义。展开更多
基金Project(60873107) supported by the National Natural Science Foundation of China
文摘The conventional deadline and budget constrained (DBC) scheduling heuristics for economic-based computational grids does not take the inconsistency of grid heterogeneity into account, which can lead to decline of application completion ratios. Motivated by this fact, a novel DI3C scheduling heuristics was proposed to deal with sequential workflow applications. In order to valuate the inconsistency, the relative cost (RC) metric was introduced, which was used to indicate the task-starving degree for resources. The new algorithm assigns tasks to resources, considering completion time, budget and RC together. The GridSim toolkit and the benchmark suites of the standard performance evaluation corporation (SPEC) were used to simulate the heterogeneous grid environment and applications. The experimental results show that the task and workflow completion ratios of the new heuristics are higher than those of the conventional heuristics.
文摘In China,the primary energy bases and the energyrequirement areas are mismatched,which presents theremote and reverse distribution characteristics,and thelarge-scale power flow is from the west to the cast andfrom the north to the south.In this paper,according tothe above characteristics and the power flow pattern,thelarge-scale,high-efficiency and long-distance UHVACand UHVDC combined transmission scheme is investi-gated and proposed,and the development mode ofChina's power grid and the planning scheme of‘NorthChina-Central China-East China'synchronous UHV gridwhich can satisfy the healthy and sustainabledevelopment of China's economy and society is proposedand optimized.
文摘为了有效集成基于主体的模型(Agent Based Model,ABM)和地理信息系统(Geographical Information System,GIS),将经典地理信息系统的功能从着重宏观地理格局的描述扩展到注重微观行为机制的刻画,作者提出并设计了一个具备网格计算能力的集成化城市微模拟平台---Grid ABGIS。首先回顾了目前城市微模拟研究进展,通过对城市微模拟系统信息过程进行归纳和总结,从软件工程的角度提出了"七步法"城市模拟信息工程的基本框架;其次分析了通用多主体城市模拟软件平台Grid ABGIS的信息处理流程和相应的系统需求;最后对Grid ABGIS的系统结构、对象体系结构、数据模型和城市主体对象模板进行了详细设计,进而实现了一个ABGIS原型系统。
文摘针对无线传感器网络占空比MAC协议在链路或节点失效环境下易导致严重的能量浪费问题,提出了一种基于Grid Quorum的异步低占空比M AC协议-AGQ-M AC(Asynchronous Grid Quorum M AC).AGQ-M AC采用Grid Quorum组分配信道,通过动态调配Quorum比率得到了节点的最优占空比,并在邻节点发现过程中采用双前导序文抽样来监测信道状态,以减少节点唤醒时间从而达到能量高效.仿真实验结果表明,与其他占空比MAC协议相比,AGQ-MAC延长了网络生存时间,降低了网络能耗,提高了邻发现数据传输率,同时保持较低的平均邻发现延迟.
文摘针对格网DEM难以对黄土高原梯田地形进行有效数字表达的问题,基于面向对象思想提出了能够顾及梯田地形的Grid-TIN混合格网DEM(Grid-TIN based DEM,GT-DEM)概念及其数据模型,并阐明其主要特征及与传统DEM的关系。以陕西绥德县辛店沟小流域水平梯田为例,利用现有1∶1万格网DEM、梯田特征点线及其外围边界线,构建出能够充分顾及梯田地形的GT-DEM。研究表明,利用现有格网DEM和梯田地形特征点线构建顾及梯田地形GT-DEM的技术可行。GT-DEM不仅可对研究区全局地形进行粗略表达,而且可对其局部梯田地形进行精细表达。该研究是对如何提高DEM的梯田地形数字表达能力的有益探索,对进一步提高DEM对淤地坝、鱼鳞坑等其他人工地形的数字表达能力具有重要借鉴意义。