期刊文献+
共找到5篇文章
< 1 >
每页显示 20 50 100
基于Hive的性能优化研究 被引量:7
1
作者 王康 陈海光 李东静 《上海师范大学学报(自然科学版)》 2017年第4期527-534,共8页
主要从Map Reduce作业调度和Hive性能调优两个方面对Hive的性能优化进行研究.对于Map Reduce主要从编程模型切入,分析其执行过程,并从map端、reduce端进行参数调优.接着从Hive框架角度入手,分别从分区表和外部表以及常用数据文件的压缩... 主要从Map Reduce作业调度和Hive性能调优两个方面对Hive的性能优化进行研究.对于Map Reduce主要从编程模型切入,分析其执行过程,并从map端、reduce端进行参数调优.接着从Hive框架角度入手,分别从分区表和外部表以及常用数据文件的压缩、行式存储与列式存储等方面进行深入研究.实验结果表明,snappy压缩、orcfile/parquet存储格式对于列式查询,提高查询效率,对于大数据分析平台有较好的兼容性. 展开更多
关键词 数据仓库 作业调优 性能 压缩 存储格式
下载PDF
货物作业车取送模型及算法研究 被引量:8
2
作者 余少鹤 李夏苗 《铁道运输与经济》 北大核心 2002年第12期46-48,共3页
合理确定取送车作业顺序,有利于减少货车在站非生产停留时间,加速车辆周转,通过对取送车作业过程的分析,将其归纳为一个典型的旅行商问题,并建立了相应的数学模型,提出了求解最优调车作业过程的启发式节约算法,并结合实例进行了验算。... 合理确定取送车作业顺序,有利于减少货车在站非生产停留时间,加速车辆周转,通过对取送车作业过程的分析,将其归纳为一个典型的旅行商问题,并建立了相应的数学模型,提出了求解最优调车作业过程的启发式节约算法,并结合实例进行了验算。此方法对优化车站各项技术作业过程有较好的实用价值。 展开更多
关键词 货车停留时间 取送车作业 旅行商问题 启发式节约算法 数学模型 作业 车辆周转 铁路运输
下载PDF
IMPROVED ACO SCHEDULING ALGORITHM BASED ON FLEXIBLE PROCESS 被引量:3
3
作者 冷晟 魏孝斌 张文艺 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2006年第2期154-160,共7页
An improved ant colony optimization (ACO) algorithm is utilized in cell scheduling of the flexible manufaturing process for considering the instrument constraint, manufacturing cost and time. Firstly, the initial we... An improved ant colony optimization (ACO) algorithm is utilized in cell scheduling of the flexible manufaturing process for considering the instrument constraint, manufacturing cost and time. Firstly, the initial weighted directional diagram is set up. Secondly, the algorithm based on the dynamic pheromone updating ensures the quick convergence and the optimal solution, thus improving the feasibility and the stability of the schedule system. Aiming at reducing collaboration with external partners, decreasing the total cost and balancing the production process, the algorithm is efficient in supporting the management process of the manufacturing cell and in strengthening the information arrangement capabitity of the scheduling system. Finally, experimental results of the improved algorithm are compared with those of other algorithms. 展开更多
关键词 manufacturing cell cell scheduling ACO PHEROMONE
下载PDF
INTEGRATED OPERATOR GENETIC ALGORITHM FOR SOLVING MULTI-OBJECTIVE FLEXIBLE JOB-SHOP SCHEDULING
4
作者 袁坤 朱剑英 +1 位作者 鞠全勇 王有远 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2006年第4期278-282,共5页
In the flexible job-shop scheduling problem (FJSP), each operation has to be assigned to a machine from a set of capable machines before alocating the assigned operations on all machines. To solve the multi-objectiv... In the flexible job-shop scheduling problem (FJSP), each operation has to be assigned to a machine from a set of capable machines before alocating the assigned operations on all machines. To solve the multi-objective FJSP, the Grantt graph oriented string representation (GOSR) and the basic manipulation of the genetic algorithm operator are presented. An integrated operator genetic algorithm (IOGA) and its process are described. Comparison between computational results and the latest research shows that the proposed algorithm is effective in reducing the total workload of all machines, the makespan and the critical machine workload. 展开更多
关键词 flexible job-shop integrated operator genetic algorithm multi-objective optimization job-shop scheduling
下载PDF
Solving Job-shop Scheduling Problem with an Ant Colony Optimization Algorithm Based on Mutation and Dynamic Pheromone Updating
5
作者 Jia Na 《Journal of Systems Science and Information》 2006年第3期443-450,共8页
The validity of the ant colony algorithm has been demonstrated as a powerful tool solving the optimization. An ant colony optimization algorithm based on mutation and dynamic pheromone updating in this paper was appli... The validity of the ant colony algorithm has been demonstrated as a powerful tool solving the optimization. An ant colony optimization algorithm based on mutation and dynamic pheromone updating in this paper was applied to settle job shop scheduling problem. Result of computer simulation shows that this method is effective. 展开更多
关键词 ant colony optimization job shop scheduling mutation algorithm
原文传递
上一页 1 下一页 到第
使用帮助 返回顶部