The purpose of this research was to develop a new approach in determination of overhaul and maintenance cost of loading equipment in surface mining. Two statistical models including univariate exponential regression (...The purpose of this research was to develop a new approach in determination of overhaul and maintenance cost of loading equipment in surface mining. Two statistical models including univariate exponential regression (UER) and multivariate linear regression (MLR) were used in this study. Loading equipment parameters such as bucket capacity, machine weight, engine power, boom length, digging depth, and dumping height were considered as variables. The results obtained by models and mean absolute error rate indicate that these models can be applied as the useful tool in determination of overhaul and maintenance cost of loading equipment. The results of this study can be used by the decision-makers for the specific surface mining operations.展开更多
In order to reduce the maintenance cost of structured Peer-to-Peer (P2P),Clone Node Protocol (CNP) based on user behavior is proposed.CNP considers the regularity of user behavior and uses the method of clone node.A B...In order to reduce the maintenance cost of structured Peer-to-Peer (P2P),Clone Node Protocol (CNP) based on user behavior is proposed.CNP considers the regularity of user behavior and uses the method of clone node.A Bidirectional Clone Node Chord model (BCNChord) based on CNP protocol is designed and realized.In BCNChord,Anticlockwise Searching Algorithm,Difference Push Synchronize Algorithm and Optimal Maintenance Algorithm are put forward to increase the performances.In experiments,according to the frequency of nodes,the maintenance cost of BCNChord can be 3.5%～32.5% lower than that of Chord.In the network of 212 nodes,the logic path hop is steady at 6,which is much more prior to 12 of Chord and 10 of CNChord.Theoretical analysis and experimental results show that BCNChord can effectively reduce the maintenance cost of its structure and simultaneously improve the query efficiency up to (1/4)O(logN).BCNChord is more suitable for highly dynamic environment and higher real-time system.展开更多
Airlines usually pay more attention to maintenance cost for efficiency improvement and consumption reduction. However, airlines, especially the domestic airlines, can hardly predict the cost exactly due to the uncerta...Airlines usually pay more attention to maintenance cost for efficiency improvement and consumption reduction. However, airlines, especially the domestic airlines, can hardly predict the cost exactly due to the uncertainty and complexity until now. In practice, the cost is calculated by collecting and calculating the invoices afterwards. To settle the problem, a maintenance cost forecasting model is proposed in this paper. Maintenance activities are classified into scheduled maintenance and unscheduled maintenance. Scheduled maintenance is periodic, in which the required materials and man-power hours can be obtained properly in advance. Nevertheless, it is impossible to acquire the necessary information of unscheduled maintenance. According to the specific characteristics of each, Activity-Based Costing (ABC) and Cost Estimating Relationships (CERs) are introduced to attack the building of forecasting models, respectively. Then practical cases, the 3C check of MD-90 and the engine shop visit are adopted to verify the cost forecasting models proposed. The results show that the models not only can predict the actual maintenance cost successfully, but also are helpful to drawing up the maintenance program and managing the maintenance funds efficiently.展开更多
文摘The purpose of this research was to develop a new approach in determination of overhaul and maintenance cost of loading equipment in surface mining. Two statistical models including univariate exponential regression (UER) and multivariate linear regression (MLR) were used in this study. Loading equipment parameters such as bucket capacity, machine weight, engine power, boom length, digging depth, and dumping height were considered as variables. The results obtained by models and mean absolute error rate indicate that these models can be applied as the useful tool in determination of overhaul and maintenance cost of loading equipment. The results of this study can be used by the decision-makers for the specific surface mining operations.
基金supported by the National Natural Science Foundation of China under Grant No.61100205Science and Technology Project of Beijing Municipal Education Commission under Grant No.KM201110016006Doctor Start-up Foundation of BUCEA under Grant No.101002508
文摘In order to reduce the maintenance cost of structured Peer-to-Peer (P2P),Clone Node Protocol (CNP) based on user behavior is proposed.CNP considers the regularity of user behavior and uses the method of clone node.A Bidirectional Clone Node Chord model (BCNChord) based on CNP protocol is designed and realized.In BCNChord,Anticlockwise Searching Algorithm,Difference Push Synchronize Algorithm and Optimal Maintenance Algorithm are put forward to increase the performances.In experiments,according to the frequency of nodes,the maintenance cost of BCNChord can be 3.5%～32.5% lower than that of Chord.In the network of 212 nodes,the logic path hop is steady at 6,which is much more prior to 12 of Chord and 10 of CNChord.Theoretical analysis and experimental results show that BCNChord can effectively reduce the maintenance cost of its structure and simultaneously improve the query efficiency up to (1/4)O(logN).BCNChord is more suitable for highly dynamic environment and higher real-time system.
文摘Airlines usually pay more attention to maintenance cost for efficiency improvement and consumption reduction. However, airlines, especially the domestic airlines, can hardly predict the cost exactly due to the uncertainty and complexity until now. In practice, the cost is calculated by collecting and calculating the invoices afterwards. To settle the problem, a maintenance cost forecasting model is proposed in this paper. Maintenance activities are classified into scheduled maintenance and unscheduled maintenance. Scheduled maintenance is periodic, in which the required materials and man-power hours can be obtained properly in advance. Nevertheless, it is impossible to acquire the necessary information of unscheduled maintenance. According to the specific characteristics of each, Activity-Based Costing (ABC) and Cost Estimating Relationships (CERs) are introduced to attack the building of forecasting models, respectively. Then practical cases, the 3C check of MD-90 and the engine shop visit are adopted to verify the cost forecasting models proposed. The results show that the models not only can predict the actual maintenance cost successfully, but also are helpful to drawing up the maintenance program and managing the maintenance funds efficiently.
