A new approach to calculate fault detection probabilities is presented. Fault-free simulation is used in the approach. The quantities of controllability and observability are defined as probabilities of controlling an...A new approach to calculate fault detection probabilities is presented. Fault-free simulation is used in the approach. The quantities of controllability and observability are defined as probabilities of controlling and observing the nodes in the circuit. The probability distribution of random signals on the circuit nodes is analyzed, and it is proved that controllability is in normal distribution. Thus the unbiasing estimation of the fault detection probability can be obtained. According to the concept of observability, we deal with the fan-out nodes. The fault coverages for actual circuits obtained from this approach agree favorably with the fault simulation results.展开更多
Software testability took a lot of interests of software community. Indeed, this concept has been interpreted in a variety of ways. One interpretation is concerned with the extent of the modifications a program compon...Software testability took a lot of interests of software community. Indeed, this concept has been interpreted in a variety of ways. One interpretation is concerned with the extent of the modifications a program component requires, so that the entire behavior of the component is observable and controllable. Another interpretation is the ease with which faults, if present in a program, can be revealed and estimated by the testing process and the propagation, infection and execution (PIE) model. It has been suggested that this particular interpretation of testability might be linked with two concepts: 1) the metric domain-to-range ratio (DRR), i.e. the ratio of the cardinality of the set of all inputs (the domain) to the cardinality of the set of all outputs (the range) and 2) the semantic fault size. First, this paper describes the connections between 1) the domain-to-range ratio and the observability and controllability aspects of testability and 2) the PIE model and fault size. The main goal of the work described here, is to seek greater understanding of testability in general and, ultimately, to find easier ways of determining it. Second, in this paper we try to model the PIE estimation using formalism for process representation system which is MAP formalism. We also use this process model to elaborate and to present the relationship between testability, PIE, DRR and fault size. Our aim is to enhance the guidance mechanisms of the process execution. After clarifying the existing relationship between semantic fault and testability, we improve the MAP model by adding qualitative criteria. We then offer a way to express maps to offer an automatic guidance of the map.展开更多
220 k V电网的站、线数量较多,电网拓扑复杂,如何经济、合理地配置220 k V线路的故障行波测距装置,实现故障测距功能的全覆盖,具有重要意义。该文分析线路故障电流行波可测性,采用扩展邻接矩阵对输电网各回线路和站际间的连接关系进行...220 k V电网的站、线数量较多,电网拓扑复杂,如何经济、合理地配置220 k V线路的故障行波测距装置,实现故障测距功能的全覆盖,具有重要意义。该文分析线路故障电流行波可测性,采用扩展邻接矩阵对输电网各回线路和站际间的连接关系进行抽象。以工程实际条件与可测性分析结果相结合作为必要的附加条件,将电流行波测距装置在电网的优化布置抽象为含不等式和等式约束的线性0-1规划模型,进而确定模型参数与电网拓扑参数的关系及模型求解方法,获得行波测距装置的全网最优静态布置方案。在此基础上,以每退出一套行波测距装置导致单、双端测距原理所减少的直接与间接可测线路的加权长度最小为依据,确定行波测距装置的动态装设顺序。并以某220 k V实际电网为例,验证所提算法的可行性及有效性。展开更多
基金Supported by the National Science Foundation of Chinathe Young Teacher Foundation of the Ministry of Posts and Telecommunications of China
文摘A new approach to calculate fault detection probabilities is presented. Fault-free simulation is used in the approach. The quantities of controllability and observability are defined as probabilities of controlling and observing the nodes in the circuit. The probability distribution of random signals on the circuit nodes is analyzed, and it is proved that controllability is in normal distribution. Thus the unbiasing estimation of the fault detection probability can be obtained. According to the concept of observability, we deal with the fan-out nodes. The fault coverages for actual circuits obtained from this approach agree favorably with the fault simulation results.
文摘Software testability took a lot of interests of software community. Indeed, this concept has been interpreted in a variety of ways. One interpretation is concerned with the extent of the modifications a program component requires, so that the entire behavior of the component is observable and controllable. Another interpretation is the ease with which faults, if present in a program, can be revealed and estimated by the testing process and the propagation, infection and execution (PIE) model. It has been suggested that this particular interpretation of testability might be linked with two concepts: 1) the metric domain-to-range ratio (DRR), i.e. the ratio of the cardinality of the set of all inputs (the domain) to the cardinality of the set of all outputs (the range) and 2) the semantic fault size. First, this paper describes the connections between 1) the domain-to-range ratio and the observability and controllability aspects of testability and 2) the PIE model and fault size. The main goal of the work described here, is to seek greater understanding of testability in general and, ultimately, to find easier ways of determining it. Second, in this paper we try to model the PIE estimation using formalism for process representation system which is MAP formalism. We also use this process model to elaborate and to present the relationship between testability, PIE, DRR and fault size. Our aim is to enhance the guidance mechanisms of the process execution. After clarifying the existing relationship between semantic fault and testability, we improve the MAP model by adding qualitative criteria. We then offer a way to express maps to offer an automatic guidance of the map.
文摘220 k V电网的站、线数量较多,电网拓扑复杂,如何经济、合理地配置220 k V线路的故障行波测距装置,实现故障测距功能的全覆盖,具有重要意义。该文分析线路故障电流行波可测性,采用扩展邻接矩阵对输电网各回线路和站际间的连接关系进行抽象。以工程实际条件与可测性分析结果相结合作为必要的附加条件,将电流行波测距装置在电网的优化布置抽象为含不等式和等式约束的线性0-1规划模型,进而确定模型参数与电网拓扑参数的关系及模型求解方法,获得行波测距装置的全网最优静态布置方案。在此基础上,以每退出一套行波测距装置导致单、双端测距原理所减少的直接与间接可测线路的加权长度最小为依据,确定行波测距装置的动态装设顺序。并以某220 k V实际电网为例,验证所提算法的可行性及有效性。
