A new equipment must frequently meet some target requirements. If it must meet an operational readiness (OR) requirement, R&M&S engineers must allocate the target to the lowest replaceable unit; they must cons...A new equipment must frequently meet some target requirements. If it must meet an operational readiness (OR) requirement, R&M&S engineers must allocate the target to the lowest replaceable unit; they must constantly predict and evaluate the target. In addition, R&M&S engineers must coordinate the targets between operational readiness and R&M&S. The prediction、allocation、coordination and optimization must be done again and again in the design, the calculating work loaded down with trivial details. The operational readiness CAD system (ORCADS) may provide useful support for R&M&S engineers. This paper discusses the method of OR prediction and implementation of ORCADS. A case example is provided.展开更多
Reliability, maintainability and testability (RMT) are important properties of equipment, since they have important influ- ence on operational availability and life cycle costs (LCC). There- fore, weighting and op...Reliability, maintainability and testability (RMT) are important properties of equipment, since they have important influ- ence on operational availability and life cycle costs (LCC). There- fore, weighting and optimizing the three properties are of great significance. A new approach for optimization of RMT parameters is proposed. First of all, the model for the equipment operation pro- cess is established based on the generalized stochastic Petri nets (GSPN) theory. Then, by solving the GSPN model, the quantitative relationship between operational availability and RMT parameters is obtained. Afterwards, taking history data of similar equipment and operation process into consideration, a cost model of design, manufacture and maintenance is developed. Based on operational availability, the cost model and parameters ranges, an optimization model of RMT parameters is built. Finally, the effectiveness and practicability of this approach are validated through an example.展开更多
Spare parts are critical to scheduled maintenance and fault repair, and can directly affect the readiness and combat capability of equipment. Equipmentrs capacity of carrying spares is influenced by its storage space ...Spare parts are critical to scheduled maintenance and fault repair, and can directly affect the readiness and combat capability of equipment. Equipmentrs capacity of carrying spares is influenced by its storage space and scales, so it is necessary to consider economic factors, e.g. spares cost, as well as non-economic ones, such as spares volume, mass and scale, when optimizing spares configuration. Aiming at this problem, the optimization model based on multi-constraints for carrying spares is built by METRIC theory and system analysis. Through the introduction of Lagrange factors, the spares cost is transformed to shadow price, and the optimization method for carrying spares and the dynamic adjustment policy of Lagrange factors are proposed. The result of a given example is analyzed, and demonstrates that the proposed model can be optimized with all constraints, and the research can provide a new way for carrying spares optimization.展开更多
This paper describes the characteristics of a single-base repairable inventory system and multi-indenture structure with communality and redundancy. At the base, there are a working field that has a maximum of z equip...This paper describes the characteristics of a single-base repairable inventory system and multi-indenture structure with communality and redundancy. At the base, there are a working field that has a maximum of z equipment on line and its repair channels, which mainly consist of two centers: line replaceable units (LRUs) diagnostic center and shop replaceable units (SRUs) repair center. In these two centers, the resources are finite and different. We introduce routing probabilities to express the repair relationships between resources and failed replaced units. The diagnostic time follows exponential distribution and SRU repair time follows general distribution with known average. We analyze the general model of this system, and present an approximate solution that uses two-step negative binomial approximation to obtain the expected backorders of all LRUs. The first step is fitting negative binomial distributions to the distributions of the number for all SitUs at the repair center, and the second is fitting negative binomial distributions to the convolutions of the distributions of the number for all LRUs in diagnostic and assemblydelayed. Thus, we give the approximate value of operational awilability of equipment based on this method. Finally, the results under two policies of routing probabilities are compared by the optimal curves.展开更多
文摘A new equipment must frequently meet some target requirements. If it must meet an operational readiness (OR) requirement, R&M&S engineers must allocate the target to the lowest replaceable unit; they must constantly predict and evaluate the target. In addition, R&M&S engineers must coordinate the targets between operational readiness and R&M&S. The prediction、allocation、coordination and optimization must be done again and again in the design, the calculating work loaded down with trivial details. The operational readiness CAD system (ORCADS) may provide useful support for R&M&S engineers. This paper discusses the method of OR prediction and implementation of ORCADS. A case example is provided.
文摘Reliability, maintainability and testability (RMT) are important properties of equipment, since they have important influ- ence on operational availability and life cycle costs (LCC). There- fore, weighting and optimizing the three properties are of great significance. A new approach for optimization of RMT parameters is proposed. First of all, the model for the equipment operation pro- cess is established based on the generalized stochastic Petri nets (GSPN) theory. Then, by solving the GSPN model, the quantitative relationship between operational availability and RMT parameters is obtained. Afterwards, taking history data of similar equipment and operation process into consideration, a cost model of design, manufacture and maintenance is developed. Based on operational availability, the cost model and parameters ranges, an optimization model of RMT parameters is built. Finally, the effectiveness and practicability of this approach are validated through an example.
基金supported in part by the General Armament Department Pre-research Foundation in 12th FiveYear(No.51304010206)the National Defense Pre-research Project in 13th Five-Year (No.41404050502)
文摘Spare parts are critical to scheduled maintenance and fault repair, and can directly affect the readiness and combat capability of equipment. Equipmentrs capacity of carrying spares is influenced by its storage space and scales, so it is necessary to consider economic factors, e.g. spares cost, as well as non-economic ones, such as spares volume, mass and scale, when optimizing spares configuration. Aiming at this problem, the optimization model based on multi-constraints for carrying spares is built by METRIC theory and system analysis. Through the introduction of Lagrange factors, the spares cost is transformed to shadow price, and the optimization method for carrying spares and the dynamic adjustment policy of Lagrange factors are proposed. The result of a given example is analyzed, and demonstrates that the proposed model can be optimized with all constraints, and the research can provide a new way for carrying spares optimization.
文摘This paper describes the characteristics of a single-base repairable inventory system and multi-indenture structure with communality and redundancy. At the base, there are a working field that has a maximum of z equipment on line and its repair channels, which mainly consist of two centers: line replaceable units (LRUs) diagnostic center and shop replaceable units (SRUs) repair center. In these two centers, the resources are finite and different. We introduce routing probabilities to express the repair relationships between resources and failed replaced units. The diagnostic time follows exponential distribution and SRU repair time follows general distribution with known average. We analyze the general model of this system, and present an approximate solution that uses two-step negative binomial approximation to obtain the expected backorders of all LRUs. The first step is fitting negative binomial distributions to the distributions of the number for all SitUs at the repair center, and the second is fitting negative binomial distributions to the convolutions of the distributions of the number for all LRUs in diagnostic and assemblydelayed. Thus, we give the approximate value of operational awilability of equipment based on this method. Finally, the results under two policies of routing probabilities are compared by the optimal curves.