In IaaS Cloud,different mapping relationships between virtual machines(VMs) and physical machines(PMs) cause different resource utilization,so how to place VMs on PMs to reduce energy consumption is becoming one of th...In IaaS Cloud,different mapping relationships between virtual machines(VMs) and physical machines(PMs) cause different resource utilization,so how to place VMs on PMs to reduce energy consumption is becoming one of the major concerns for cloud providers.The existing VM scheduling schemes propose optimize PMs or network resources utilization,but few of them attempt to improve the energy efficiency of these two kinds of resources simultaneously.This paper proposes a VM scheduling scheme meeting multiple resource constraints,such as the physical server size(CPU,memory,storage,bandwidth,etc.) and network link capacity to reduce both the numbers of active PMs and network elements so as to finally reduce energy consumption.Since VM scheduling problem is abstracted as a combination of bin packing problem and quadratic assignment problem,which is also known as a classic combinatorial optimization and NP-hard problem.Accordingly,we design a twostage heuristic algorithm to solve the issue,and the simulations show that our solution outperforms the existing PM- or network-only optimization solutions.展开更多
As a constraint for smart devices,energy consumption has attract people's attention for a long time period. How to get higher resource utilization with less energy consumption is a challenge for cognitive radio ne...As a constraint for smart devices,energy consumption has attract people's attention for a long time period. How to get higher resource utilization with less energy consumption is a challenge for cognitive radio networks. Secondary users have to participate in spectrum sensing at the cost of energy and access idle spectrum without interfering primary users. However,not all participating secondary users can access idle spectrum. How to ensure the participation users access spectrum efficiently with a larger probability is an urgent problem to be solved. We propose an Energy Efficiency-based Decision Making(EEDM) for cognitive radio networks,which fully considers residual energy and probability of obtaining spectrum resources. Simulation and analysis show that the proposed scheme can maximize proportion of allocated users under the premise of ensuring the accuracy of spectrum sensing,then balance users' energy consumption and access efficiency,so as to effectively improve the utilization of spectrum resources.展开更多
Reasonable ＂eco-city＂in the external between urban and rural areas should make a complete ecological cycle of the system, so that the internal energy efficiency and low pollution, resource use environmentally clean,...Reasonable ＂eco-city＂in the external between urban and rural areas should make a complete ecological cycle of the system, so that the internal energy efficiency and low pollution, resource use environmentally clean, quiet comfortable life of the people, as well as other elements of the organic： unity of urban greening. So, ＂Eco-City＂, ＂urban ecology＂ are two heterogeneous areas should be treated differently. However, in rural and urban dualistic situation, China advocated ＂ecological city＂ ignored the rural ecological balance, resulting in ＂eco-city＂development directly into＂ urban ecology＂ construction within the city along with the waste of resources, water pollution, serious problems of air pollution, noise pollution, the deep ＂eco-city＂ into representation＂ urban ecology＂, in the standard does not cover up the sound, making the generation between rural and urban＂ material Rift ,＂after all ,can not be filled.展开更多
基金the National Natural Science Foundation of China，the National High Technology Research and Development Program of China (863 Program)，the Fundamental Research Funds for the Central Universities，the Natural Science Foundation of Gansu Province,China，the Open Fund of the State Key Laboratory of Software Development Environment
文摘In IaaS Cloud,different mapping relationships between virtual machines(VMs) and physical machines(PMs) cause different resource utilization,so how to place VMs on PMs to reduce energy consumption is becoming one of the major concerns for cloud providers.The existing VM scheduling schemes propose optimize PMs or network resources utilization,but few of them attempt to improve the energy efficiency of these two kinds of resources simultaneously.This paper proposes a VM scheduling scheme meeting multiple resource constraints,such as the physical server size(CPU,memory,storage,bandwidth,etc.) and network link capacity to reduce both the numbers of active PMs and network elements so as to finally reduce energy consumption.Since VM scheduling problem is abstracted as a combination of bin packing problem and quadratic assignment problem,which is also known as a classic combinatorial optimization and NP-hard problem.Accordingly,we design a twostage heuristic algorithm to solve the issue,and the simulations show that our solution outperforms the existing PM- or network-only optimization solutions.
基金supported by the National Natural Science Foundation of China (NO.61602358,No.61373170,NO.U1401251,No.U1536202)Fundamental Research Funds for the Central Universities(No.JB150114)the Natural Science Basic Research Plan in Shaanxi Province,China (No.2014JQ8308)
文摘As a constraint for smart devices,energy consumption has attract people's attention for a long time period. How to get higher resource utilization with less energy consumption is a challenge for cognitive radio networks. Secondary users have to participate in spectrum sensing at the cost of energy and access idle spectrum without interfering primary users. However,not all participating secondary users can access idle spectrum. How to ensure the participation users access spectrum efficiently with a larger probability is an urgent problem to be solved. We propose an Energy Efficiency-based Decision Making(EEDM) for cognitive radio networks,which fully considers residual energy and probability of obtaining spectrum resources. Simulation and analysis show that the proposed scheme can maximize proportion of allocated users under the premise of ensuring the accuracy of spectrum sensing,then balance users' energy consumption and access efficiency,so as to effectively improve the utilization of spectrum resources.
文摘Reasonable ＂eco-city＂in the external between urban and rural areas should make a complete ecological cycle of the system, so that the internal energy efficiency and low pollution, resource use environmentally clean, quiet comfortable life of the people, as well as other elements of the organic： unity of urban greening. So, ＂Eco-City＂, ＂urban ecology＂ are two heterogeneous areas should be treated differently. However, in rural and urban dualistic situation, China advocated ＂ecological city＂ ignored the rural ecological balance, resulting in ＂eco-city＂development directly into＂ urban ecology＂ construction within the city along with the waste of resources, water pollution, serious problems of air pollution, noise pollution, the deep ＂eco-city＂ into representation＂ urban ecology＂, in the standard does not cover up the sound, making the generation between rural and urban＂ material Rift ,＂after all ,can not be filled.
