As one of the key technologies of cloud computing,the virtualization technology can virtualize all kinds of resources and integrate them into the unified planning of the cloud computing management platform.The migrati...As one of the key technologies of cloud computing,the virtualization technology can virtualize all kinds of resources and integrate them into the unified planning of the cloud computing management platform.The migration of virtual machines is one of the important technologies of virtual machine applications.However,there are still many deficiencies in the implementation of load balancing by virtual machine dynamic migration in cloud computing.Traditional triggering strategy thresholds are mostly fixed.If there is an instantaneous peak,it will cause migration,which will cause a waste of resources.In order to solve this problem,based on improving the dynamic migration framework,this paper proposes node selection optimization algorithm and node load balancing strategy and designs a prediction module,which uses a one-time smooth prediction to avoid the shortcoming of peak load moment.The simulation experiments and conclusions analysis results show that the fusion algorithm has performance advantages obvious.展开更多
The continuous growth of air traffic has led to acute airspace congestion and severe delays, which threatens operation safety and cause enormous economic loss. Flight assignment is an economical and effective strategi...The continuous growth of air traffic has led to acute airspace congestion and severe delays, which threatens operation safety and cause enormous economic loss. Flight assignment is an economical and effective strategic plan to reduce the flight delay and airspace congestion by rea- sonably regulating the air traffic flow of China. However, it is a large-scale combinatorial optimiza- tion problem which is difficult to solve. In order to improve the quality of solutions, an effective multi-objective parallel evolution algorithm （MPEA） framework with dynamic migration interval strategy is presented in this work. Firstly, multiple evolution populations are constructed to solve the problem simultaneously to enhance the optimization capability. Then a new strategy is pro- posed to dynamically change the migration interval among different evolution populations to improve the efficiency of the cooperation of populations. Finally, the cooperative co-evolution （CC） algorithm combined with non-dominated sorting genetic algorithm II （NSGA-II） is intro- duced for each population. Empirical studies using the real air traffic data of the Chinese air route network and daily flight plans show that our method outperforms the existing approaches, multi- objective genetic algorithm （MOGA）, multi-objective evolutionary algorithm based on decom- position （MOEA/D）, CC-based multi-objective algorithm （CCMA） as well as other two MPEAs with different migration interval strategies.展开更多
MPSoC （multi-processor systems on-chip） are going to be the leading hardware platform featured in embedded systems, The complexity of multimedia applications implemented on MPSoC and the requirements of users compli...MPSoC （multi-processor systems on-chip） are going to be the leading hardware platform featured in embedded systems, The complexity of multimedia applications implemented on MPSoC and the requirements of users complicate the designer＇s job to conceive and deliver efficient systems in the shortest time. MPSoC dedicated to specific embedded applications are facing constraints of performance and cost. In this context, in order to improve the performance of these systems, we propose a methodology for dynamic task migration in dedicated MPSoC. This methodology aims to improve the performance of execution and also reduction of energy consumption. We propose in this paper, an estimation of the real-time energy （line）. This approach is structured on four steps： （1） modeling software; （2） mapping and execution; （3） performance evaluation; （4） migration. We have using the Soclib tool to determine performance estimation of migrating software task to hardware component. Experiments on MJPEG decoder are made to illustrate the efficiency of our approach in performance estimation.展开更多
In order to study the characters of chemical kinetics for organophosphorus migration in clay with different pH, waste of organophosphorus was put under pressure to leakage permeating the cohesive soil, and simulate th...In order to study the characters of chemical kinetics for organophosphorus migration in clay with different pH, waste of organophosphorus was put under pressure to leakage permeating the cohesive soil, and simulate the process of organophosphorus leakage permeating the Aquitard, searching the characters of chemical kinetics for organophosphorus migration in clay with different pH. It is shown that the ability of migration of organophosphorus leakage permeating the cohesive soil fall with increase of pH; the penetration rate of organophosphorus is about 1.25% when pH is 7.5, organophosphorus has not penetrated the cohesive soil when pH is equal or greater than 8.5. The effect of retardarce is obvious. Concentration of PO43？ that comes from the mineralization of organophosphorus is lowered slightly with increases of pH of clay, and rise with extension of time. The Chemical Kinetics equation is log c=-0.1pH＋0.2172k1t＋S.展开更多
The performance degradation mechanism of ceramic fuel cell with NCAL(Ni_(0.8)Co_(0.15)Al_(0.05)LiO_(2))as symmetrical electrode and GDC as electrolyte in H2 is investigated.It is found that under the condition of 550◦...The performance degradation mechanism of ceramic fuel cell with NCAL(Ni_(0.8)Co_(0.15)Al_(0.05)LiO_(2))as symmetrical electrode and GDC as electrolyte in H2 is investigated.It is found that under the condition of 550◦C and constant current density of 0.2 A⋅cm^(-2),the output voltage of the cell is about 1.005 V in the initial 10 h and remains relatively stable.After 10 h,the voltage of the cell began to decrease gradually,and by 50 h,the voltage had decreased to 0.522 V.The results testing electrochemical performance of the cell and characterizing the cell materials before and after test using SEM,TOF-SIMS and FTIR indicate that the distribution of Li_(2)O/LiOH/Li_(2)CO_(3)compounds generated from NCAL anode in the cell plays a vital role in significantly improving the ionic conductivity of electrolyte and gas tightness of the cell.The dynamic migration of molten salt destroyed the continuity of molten salt in the cell,which in turn adversely impacted the ionic conductivity of electrolyte,gas tightness of the cell,and electrochemical reactions on both sides of the cathode and anode.These finally lead to the degradation of the cell performance.展开更多
Structural reconstruction of nanomaterials offers a fantastic way to regulate the electronic structure of active sites and promote their catalytic activities.However,how to properly facilitate surface reconstruction t...Structural reconstruction of nanomaterials offers a fantastic way to regulate the electronic structure of active sites and promote their catalytic activities.However,how to properly facilitate surface reconstruction to overcome large overpotential that stimulate the surface reconstruction has remained elusive.Herein,we adopt a facile approach to activate surface reconstruction on Ni(OH)_(2) by incorporating F anions to achieve electro-derived structural oxidation process and further boost its oxygen evolution reaction(OER)activity.Ex situ Raman and X-ray photoemission spectroscopy studies indicate that F ions incorporation facilitated surface reconstruction and promotes the original Ni(OH)_(2)transformed into a mesoporous and amorphous F-NiOOH layer during the electrochemical process.Density functional theory(DFT)calculation reveals that this self-reconstructed NiOOH induces a space-charge effect on the p-n junction interface,which not only promotes the absorption of intermediates species(^(*)OH,^(*)O,and^(*)OOH)and charge-transfer process during catalysis,but also leads to a strong interaction of the p-n junction interface to stabilize the materials.This work opens up a new possibility to regulate the electronic structure of active sites and promote their catalytic activities.展开更多
基金supported by the National Natural Science Foundation of China(61772196,61472136)the Hunan Provincial Focus Social Science Fund(2016ZDB006)+2 种基金Hunan Provincial Social Science Achievement Review Committee results in appraisal identification project(Xiang social assessment 2016JD05)Key Project of Hunan Provincial Social Science Achievement Review Committee(XSP 19ZD1005)The authors gratefully acknowledge the financial support provided by the Key Laboratory of Hunan Province for New Retail Virtual Reality Technology(2017TP1026).
文摘As one of the key technologies of cloud computing,the virtualization technology can virtualize all kinds of resources and integrate them into the unified planning of the cloud computing management platform.The migration of virtual machines is one of the important technologies of virtual machine applications.However,there are still many deficiencies in the implementation of load balancing by virtual machine dynamic migration in cloud computing.Traditional triggering strategy thresholds are mostly fixed.If there is an instantaneous peak,it will cause migration,which will cause a waste of resources.In order to solve this problem,based on improving the dynamic migration framework,this paper proposes node selection optimization algorithm and node load balancing strategy and designs a prediction module,which uses a one-time smooth prediction to avoid the shortcoming of peak load moment.The simulation experiments and conclusions analysis results show that the fusion algorithm has performance advantages obvious.
基金co-supported by the Foundation for Innovative Research Groups of the National Natural Science Foundation of China (No. 60921001)
文摘The continuous growth of air traffic has led to acute airspace congestion and severe delays, which threatens operation safety and cause enormous economic loss. Flight assignment is an economical and effective strategic plan to reduce the flight delay and airspace congestion by rea- sonably regulating the air traffic flow of China. However, it is a large-scale combinatorial optimiza- tion problem which is difficult to solve. In order to improve the quality of solutions, an effective multi-objective parallel evolution algorithm （MPEA） framework with dynamic migration interval strategy is presented in this work. Firstly, multiple evolution populations are constructed to solve the problem simultaneously to enhance the optimization capability. Then a new strategy is pro- posed to dynamically change the migration interval among different evolution populations to improve the efficiency of the cooperation of populations. Finally, the cooperative co-evolution （CC） algorithm combined with non-dominated sorting genetic algorithm II （NSGA-II） is intro- duced for each population. Empirical studies using the real air traffic data of the Chinese air route network and daily flight plans show that our method outperforms the existing approaches, multi- objective genetic algorithm （MOGA）, multi-objective evolutionary algorithm based on decom- position （MOEA/D）, CC-based multi-objective algorithm （CCMA） as well as other two MPEAs with different migration interval strategies.
文摘MPSoC （multi-processor systems on-chip） are going to be the leading hardware platform featured in embedded systems, The complexity of multimedia applications implemented on MPSoC and the requirements of users complicate the designer＇s job to conceive and deliver efficient systems in the shortest time. MPSoC dedicated to specific embedded applications are facing constraints of performance and cost. In this context, in order to improve the performance of these systems, we propose a methodology for dynamic task migration in dedicated MPSoC. This methodology aims to improve the performance of execution and also reduction of energy consumption. We propose in this paper, an estimation of the real-time energy （line）. This approach is structured on four steps： （1） modeling software; （2） mapping and execution; （3） performance evaluation; （4） migration. We have using the Soclib tool to determine performance estimation of migrating software task to hardware component. Experiments on MJPEG decoder are made to illustrate the efficiency of our approach in performance estimation.
基金supported by the Knowledge Innovation Programs of Chinese Academy of Sciences(No.KZCX2YWQ062,KZCX2YW126)
文摘In order to study the characters of chemical kinetics for organophosphorus migration in clay with different pH, waste of organophosphorus was put under pressure to leakage permeating the cohesive soil, and simulate the process of organophosphorus leakage permeating the Aquitard, searching the characters of chemical kinetics for organophosphorus migration in clay with different pH. It is shown that the ability of migration of organophosphorus leakage permeating the cohesive soil fall with increase of pH; the penetration rate of organophosphorus is about 1.25% when pH is 7.5, organophosphorus has not penetrated the cohesive soil when pH is equal or greater than 8.5. The effect of retardarce is obvious. Concentration of PO43？ that comes from the mineralization of organophosphorus is lowered slightly with increases of pH of clay, and rise with extension of time. The Chemical Kinetics equation is log c=-0.1pH＋0.2172k1t＋S.
基金supported by the National Natural Science Foundation of China(No.21978044).
文摘The performance degradation mechanism of ceramic fuel cell with NCAL(Ni_(0.8)Co_(0.15)Al_(0.05)LiO_(2))as symmetrical electrode and GDC as electrolyte in H2 is investigated.It is found that under the condition of 550◦C and constant current density of 0.2 A⋅cm^(-2),the output voltage of the cell is about 1.005 V in the initial 10 h and remains relatively stable.After 10 h,the voltage of the cell began to decrease gradually,and by 50 h,the voltage had decreased to 0.522 V.The results testing electrochemical performance of the cell and characterizing the cell materials before and after test using SEM,TOF-SIMS and FTIR indicate that the distribution of Li_(2)O/LiOH/Li_(2)CO_(3)compounds generated from NCAL anode in the cell plays a vital role in significantly improving the ionic conductivity of electrolyte and gas tightness of the cell.The dynamic migration of molten salt destroyed the continuity of molten salt in the cell,which in turn adversely impacted the ionic conductivity of electrolyte,gas tightness of the cell,and electrochemical reactions on both sides of the cathode and anode.These finally lead to the degradation of the cell performance.
基金This work was funded by the Science and Technology Development Fund,Macao SAR(Nos.0191/2017/A3,0041/2019/A1,0046/2019/AFJ,and 0021/2019/AIR)University of Macao(Nos.MYRG2017-00216-FST and MYRG2018-00192-IAPME)+3 种基金UEA funding,the National Natural Science Foundation of China(Nos.51773211 and 21961160700)the Beijing Municipal Science&Technology Commission,the IBS(IBS-R019-D1)the State Key Laboratory of Organic-Inorganic Composites(OIC)(No.202101002)The DFT calculations were performed at High Performance Computing Cluster(HPCC)of Information and Communication Technology Office(ICTO)at University of Macao.
文摘Structural reconstruction of nanomaterials offers a fantastic way to regulate the electronic structure of active sites and promote their catalytic activities.However,how to properly facilitate surface reconstruction to overcome large overpotential that stimulate the surface reconstruction has remained elusive.Herein,we adopt a facile approach to activate surface reconstruction on Ni(OH)_(2) by incorporating F anions to achieve electro-derived structural oxidation process and further boost its oxygen evolution reaction(OER)activity.Ex situ Raman and X-ray photoemission spectroscopy studies indicate that F ions incorporation facilitated surface reconstruction and promotes the original Ni(OH)_(2)transformed into a mesoporous and amorphous F-NiOOH layer during the electrochemical process.Density functional theory(DFT)calculation reveals that this self-reconstructed NiOOH induces a space-charge effect on the p-n junction interface,which not only promotes the absorption of intermediates species(^(*)OH,^(*)O,and^(*)OOH)and charge-transfer process during catalysis,but also leads to a strong interaction of the p-n junction interface to stabilize the materials.This work opens up a new possibility to regulate the electronic structure of active sites and promote their catalytic activities.
