能源转型背景下新能源的迅猛发展给电力系统带来更多不确定性,如何评估在此形势下电网规划方案的合理性是一项重大挑战。输电线路利用率是评价输电资源利用的关键指标,但传统利用率指标通常以热稳定极限功率为参照,忽略了电网运行状态...能源转型背景下新能源的迅猛发展给电力系统带来更多不确定性,如何评估在此形势下电网规划方案的合理性是一项重大挑战。输电线路利用率是评价输电资源利用的关键指标,但传统利用率指标通常以热稳定极限功率为参照,忽略了电网运行状态对线路输电能力的影响,无法从指标本身分析输电资源利用水平受限的原因。在系统安全约束限制下,输电线路最大输电能力(total transfer capability,TTC)一般小于热稳定极限功率。对输电线路TTC的计算方法进行了研究,以最优潮流模型为基础,从单时段和多时段两方面分别计算输电线路在系统安全约束下的TTC,同时设计线性化方法降低模型求解难度。然后基于输电线路TTC,提出能够有效表征输电线路资源利用水平的改进利用率计算方法。最后,算例分析对输电线路TTC进行了讨论,对输电线路合理利用率做出评估分析,得出输电资源利用水平受限原因,验证了所提模型和方法的合理性与有效性。展开更多
Many Task Computing(MTC)is a new class of computing paradigm in which the aggregate number of tasks,quantity of computing,and volumes of data may be extremely large.With the advent of Cloud computing and big data era,...Many Task Computing(MTC)is a new class of computing paradigm in which the aggregate number of tasks,quantity of computing,and volumes of data may be extremely large.With the advent of Cloud computing and big data era,scheduling and executing large-scale computing tasks efficiently and allocating resources to tasks reasonably are becoming a quite challenging problem.To improve both task execution and resource utilization efficiency,we present a task scheduling algorithm with resource attribute selection,which can select the optimal node to execute a task according to its resource requirements and the fitness between the resource node and the task.Experiment results show that there is significant improvement in execution throughput and resource utilization compared with the other three algorithms and four scheduling frameworks.In the scheduling algorithm comparison,the throughput is 77%higher than Min-Min algorithm and the resource utilization can reach 91%.In the scheduling framework comparison,the throughput(with work-stealing)is at least 30%higher than the other frameworks and the resource utilization reaches 94%.The scheduling algorithm can make a good model for practical MTC applications.展开更多
In order to reasonably utilize the iron resources of copper slags, the smelting chlorination process was used to remove copper from copper slags. Higher holding temperature and O2 flow rate are beneficial to increasin...In order to reasonably utilize the iron resources of copper slags, the smelting chlorination process was used to remove copper from copper slags. Higher holding temperature and O2 flow rate are beneficial to increasing copper removal rate. However,the Cu2O mode is formed by the reaction of surplus O2 and CuCl with O2 flow rate increasing over 0.4 L/min, causing CuCl volatilization rate and copper removal rate to decrease. The resulting copper removal rate of 84.34% is obtained under the optimum conditions of holding temperature of 1573 K, residence time of 10 min, Ca Cl2 addition amount of 0.1(mass ratio of CaCl2 and the copper slag) and oxygen flow rate of 0.4 L/min. The efficient removal of copper from copper slags through chlorination is feasible.展开更多
文摘能源转型背景下新能源的迅猛发展给电力系统带来更多不确定性,如何评估在此形势下电网规划方案的合理性是一项重大挑战。输电线路利用率是评价输电资源利用的关键指标,但传统利用率指标通常以热稳定极限功率为参照,忽略了电网运行状态对线路输电能力的影响,无法从指标本身分析输电资源利用水平受限的原因。在系统安全约束限制下,输电线路最大输电能力(total transfer capability,TTC)一般小于热稳定极限功率。对输电线路TTC的计算方法进行了研究,以最优潮流模型为基础,从单时段和多时段两方面分别计算输电线路在系统安全约束下的TTC,同时设计线性化方法降低模型求解难度。然后基于输电线路TTC,提出能够有效表征输电线路资源利用水平的改进利用率计算方法。最后,算例分析对输电线路TTC进行了讨论,对输电线路合理利用率做出评估分析,得出输电资源利用水平受限原因,验证了所提模型和方法的合理性与有效性。
基金ACKNOWLEDGEMENTS The authors would like to thank the reviewers for their detailed reviews and constructive comments, which have helped improve the quality of this paper. The research has been partly supported by National Natural Science Foundation of China No. 61272528 and No. 61034005, and the Central University Fund （ID-ZYGX2013J073）.
文摘Many Task Computing(MTC)is a new class of computing paradigm in which the aggregate number of tasks,quantity of computing,and volumes of data may be extremely large.With the advent of Cloud computing and big data era,scheduling and executing large-scale computing tasks efficiently and allocating resources to tasks reasonably are becoming a quite challenging problem.To improve both task execution and resource utilization efficiency,we present a task scheduling algorithm with resource attribute selection,which can select the optimal node to execute a task according to its resource requirements and the fitness between the resource node and the task.Experiment results show that there is significant improvement in execution throughput and resource utilization compared with the other three algorithms and four scheduling frameworks.In the scheduling algorithm comparison,the throughput is 77%higher than Min-Min algorithm and the resource utilization can reach 91%.In the scheduling framework comparison,the throughput(with work-stealing)is at least 30%higher than the other frameworks and the resource utilization reaches 94%.The scheduling algorithm can make a good model for practical MTC applications.
基金Project(51204082)supported by the National Natural Science Foundation of ChinaProject(KKZ3201252011)supported by Talent Cultivation Project of Kunming University of Science and Technology,China
文摘In order to reasonably utilize the iron resources of copper slags, the smelting chlorination process was used to remove copper from copper slags. Higher holding temperature and O2 flow rate are beneficial to increasing copper removal rate. However,the Cu2O mode is formed by the reaction of surplus O2 and CuCl with O2 flow rate increasing over 0.4 L/min, causing CuCl volatilization rate and copper removal rate to decrease. The resulting copper removal rate of 84.34% is obtained under the optimum conditions of holding temperature of 1573 K, residence time of 10 min, Ca Cl2 addition amount of 0.1(mass ratio of CaCl2 and the copper slag) and oxygen flow rate of 0.4 L/min. The efficient removal of copper from copper slags through chlorination is feasible.
