摘要 :
In this paper, the problems of qualitative analysis using failure mode, effects and criticality analysis method (FMECA) are studied based on the current database of aircraft mechanical products. The feasibility research of improvi...
展开
In this paper, the problems of qualitative analysis using failure mode, effects and criticality analysis method (FMECA) are studied based on the current database of aircraft mechanical products. The feasibility research of improving the traditional FMECA method with Analytic Hierarchy Process method (AHP) is presented. The scale effects of AHP is analyzed, and the index scale method is selected. The steps of improved FMECA method based on AHP are discussed, and the comparative analysis of the results obtained from the new and the traditional methods is performed combining with available cases. It is suggested that more accurate list of reliable key product can be obtained using the new method compared with using the traditional FMECA method, under the condition of the imperfect existing database.
收起
摘要 :
In this paper, the problems of qualitative analysis using failure mode, effects and criticality analysis method (FMECA) are studied based on the current database of aircraft mechanical products. The feasibility research of improvi...
展开
In this paper, the problems of qualitative analysis using failure mode, effects and criticality analysis method (FMECA) are studied based on the current database of aircraft mechanical products. The feasibility research of improving the traditional FMECA method with Analytic Hierarchy Process method (AHP) is presented. The scale effects of AHP is analyzed, and the index scale method is selected. The steps of improved FMECA method based on AHP are discussed, and the comparative analysis of the results obtained from the new and the traditional methods is performed combining with available cases. It is suggested that more accurate list of reliable key product can be obtained using the new method compared with using the traditional FMECA method, under the condition of the imperfect existing database.
收起
摘要 :
In wireless sensor networks(WSNs),most sleep scheduling mechanisms are designed for resource-constrained terminal nodes and few sleep schemes are optimized for routing nodes.In this paper,we present a sleep scheduling mechanism fo...
展开
In wireless sensor networks(WSNs),most sleep scheduling mechanisms are designed for resource-constrained terminal nodes and few sleep schemes are optimized for routing nodes.In this paper,we present a sleep scheduling mechanism for the routing nodes and their next hop neighbors.According to the number and sleep cycles of next hop neighbors,the routing nodes can set their own sleep cycles by an adaptive sleep cycle algorithm with the purpose of minimizing the energy consumption of the routing nodes as well as reducing their next hop neighbors' energy consumption.The test results demonstrate that the proposed mechanism prolongs the network lifetime effectively and is suitable for different scenarios.
收起
摘要 :
In wireless sensor networks(WSNs),most sleep scheduling mechanisms are designed for resource-constrained terminal nodes and few sleep schemes are optimized for routing nodes.In this paper,we present a sleep scheduling mechanism fo...
展开
In wireless sensor networks(WSNs),most sleep scheduling mechanisms are designed for resource-constrained terminal nodes and few sleep schemes are optimized for routing nodes.In this paper,we present a sleep scheduling mechanism for the routing nodes and their next hop neighbors.According to the number and sleep cycles of next hop neighbors,the routing nodes can set their own sleep cycles by an adaptive sleep cycle algorithm with the purpose of minimizing the energy consumption of the routing nodes as well as reducing their next hop neighbors' energy consumption.The test results demonstrate that the proposed mechanism prolongs the network lifetime effectively and is suitable for different scenarios.
收起
摘要 :
An efficiency optimization control strategy of the direct torque controlled interior permanent magnet synchronous motors is proposed. Firstly, the mathematical model of the IPMSM is established in the rotor frame considering iron ...
展开
An efficiency optimization control strategy of the direct torque controlled interior permanent magnet synchronous motors is proposed. Firstly, the mathematical model of the IPMSM is established in the rotor frame considering iron losses. Secondly, the function relationship between the power losses and the output torque, speed and stator flux is analyzed, and the computational formula of the stator flux amplitude which makes the power losses minimization is derived under different operating conditions. Consequently, the efficiency optimization control for direct torque controlled IPMSM driving systems is achieved. The experimental results show that the proposed control method not only preserves the fast torque dynamic response of the conventional direct torque control, but also improves operating efficiency of the driving system.
收起
摘要 :
An efficiency optimization control strategy of the direct torque controlled interior permanent magnet synchronous motors is proposed. Firstly, the mathematical model of the IPMSM is established in the rotor frame considering iron ...
展开
An efficiency optimization control strategy of the direct torque controlled interior permanent magnet synchronous motors is proposed. Firstly, the mathematical model of the IPMSM is established in the rotor frame considering iron losses. Secondly, the function relationship between the power losses and the output torque, speed and stator flux is analyzed, and the computational formula of the stator flux amplitude which makes the power losses minimization is derived under different operating conditions. Consequently, the efficiency optimization control for direct torque controlled IPMSM driving systems is achieved. The experimental results show that the proposed control method not only preserves the fast torque dynamic response of the conventional direct torque control, but also improves operating efficiency of the driving system.
收起
摘要 :
An efficiency optimization control strategy of the direct torque controlled interior permanent magnet synchronous motors is proposed. Firstly, the mathematical model of the IPMSM is established in the rotor frame considering iron ...
展开
An efficiency optimization control strategy of the direct torque controlled interior permanent magnet synchronous motors is proposed. Firstly, the mathematical model of the IPMSM is established in the rotor frame considering iron losses. Secondly, the function relationship between the power losses and the output torque, speed and stator flux is analyzed, and the computational formula of the stator flux amplitude which makes the power losses minimization is derived under different operating conditions. Consequently, the efficiency optimization control for direct torque controlled IPMSM driving systems is achieved. The experimental results show that the proposed control method not only preserves the fast torque dynamic response of the conventional direct torque control, but also improves operating efficiency of the driving system.
收起
摘要 :
As the time of system running increases, the performance of the system will decrease. This phenomenon is called software aging. Recently software rejuvenation as an efficient method to counteract software aging emerges. This metho...
展开
As the time of system running increases, the performance of the system will decrease. This phenomenon is called software aging. Recently software rejuvenation as an efficient method to counteract software aging emerges. This method recovers the performance of the system through cleaning the internal state of system. Now component-oriented programming concept has been proposed and spreaded. And software system based on component emerges. These components with different function not only promote software reusability and self-management but also software reliability and availability. This paper demonstrates a software rejuvenation model based on resource-aware component optimized scheduling to realize software rejuvenation and avoid system crashing. In this paper we give the Lagrangian Relaxation component scheduling algorithm under single constrained condition and multi constrained condition. Then we test the algorithm and evaluate the model. Comparing system reboot, this rejuvenation model reduces MTTR (mean time to recover) very much. So the continuity of the service is promoted and the cost of downtime is decreased.
收起
摘要 :
Frequent itemset mining is a fundamental and essential issue in data mining field and can be used in many data mining tasks. Most of these mining tasks require multiple passes over the database and if the database size is large, w...
展开
Frequent itemset mining is a fundamental and essential issue in data mining field and can be used in many data mining tasks. Most of these mining tasks require multiple passes over the database and if the database size is large, which is usually the case, scalable high performance solutions involving multiple processors are required. In this paper, we present a novel parallel frequent itemset mining algorithm which is called HPFP-Miner. The proposed algorithm is based on FP-Growth and introduces little communication overheads by efficiently partitioning the list of frequent elements list over processors. The results of experiment show that HPFP-Miner has good scalability and performance.
收起
摘要 :
Frequent itemset mining is a fundamental and essential issue in data mining field and can be used in many data mining tasks. Most of these mining tasks require multiple passes over the database and if the database size is large, w...
展开
Frequent itemset mining is a fundamental and essential issue in data mining field and can be used in many data mining tasks. Most of these mining tasks require multiple passes over the database and if the database size is large, which is usually the case, scalable high performance solutions involving multiple processors are required. In this paper, we present a novel parallel frequent itemset mining algorithm which is called HPFP-Miner. The proposed algorithm is based on FP-Growth and introduces little communication overheads by efficiently partitioning the list of frequent elements list over processors. The results of experiment show that HPFP-Miner has good scalability and performance.
收起
原文获取