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Incorrect responses from protective devices weaken the reliability of microgrids. This paper investigates the effects of the protection system on the reliability performance of a microgrid integrated with weather-dependent microsources. It relies on a stochastic model to simulate the challenges existing in current protection schemes designed for microgrids. Abnormal operating conditions, including...
The estimation problem of the stress-strength reliability is investigated for a class of lifetime distribution based on record values. Some frequentist and Bayes estimators are derived for the stress-strength parameter, respectively. Finally, an examples is presented to illustrate the proposed methods by using Monte-Carlo method.
Proportional hazards model is introduced into dealing with accelerated degradation test data, and a model based on proportional degradation hazards model (PDHM) is proposed, the only assumption is that the logarithm of the degradation hazard function is a linear function of the stress covariates. The PDHM is established with degradation data, then the probability density function and Likelihood function...
In this paper, an advanced modulation scheme called superposition modulation (SM) and its applications in bit-interleaved coded modulation (BICM) is studied. The maximum a posteriori (MAP) detector and the probabilistic data association detector with Gaussian approximation (PDA-GA) are investigated using the extrinsic information transfer (EXIT) chart technique. It is demonstrated that the performance...
In this paper, we propose a new cooperative spectrum sensing scheme to minimize the false alarm probability while satisfying the detection probability at a desired level. To improve the spectrum sensing performance, it is desirable for the cognitive base station to combine binary local decisions of secondary users by considering the local sensing reliability. In the proposed scheme, the local decisions...
Based on the mission success requirements, the missions of the combat units are analyzed. Aim at the equipment support objects of different levels include of k-out-of-n system, equipment, basic mission units and combat mission units, the models of evaluating mission success probability are built and implemented. The research demonstrates that the method is feasible and effective to evaluate the mission...
In prediction error identification, confidence regions are most commonly derived from the asymptotic statistical properties of the parameter estimator. Therefore, these confidence regions are only asymptotically valid and, for finite samples, their actual coverage rate can be smaller than the desired coverage rate. In this paper, we analyze the influence of the SNR and of the type of model structure...
The sequential probability ratio test (SPRT) is the most common acceptance test in the field of reliability and quality control of electronic systems. Proposed are measures of the test quality. One of them is the increase in the average sample number (ASN) caused by the test truncation. An optimality criterion based on it considerably facilitates solution of the problems in automatic planning of the...
Aiming at the defect of traditional risk priority number (RPN) method in FMECA, a RPN assessment method is put forward which bases on the fault propagation probability and cost, then a corrective actions choice method is presented by gray correlation theory. Firstly, the occurrence probability and cost are calculated according to fault propagation tree. RPN is assessed by the overall risk of the events...
A probabilistic analytical framework for decentralized load balancing (LB) strategies for heterogeneous distributed-computing systems (DCSs) is presented with the overall goal of maximizing the service reliability in the presence of random failures. The service reliability of a DCS is defined as the probability of successfully serving a specified workload before all the computing nodes fail permanently...
Fuzzy reliability analysis is of great importance for structural engineering such as arch dams, large concrete dams etc. In this paper, an improved method of fuzzy reliability analysis on deep sliding surface in rock foundation under dam is established. Firstly, this paper discussed how to determine the probability density function of structure. Secondly, according to the knowledge of fuzzy mathematics...
In this paper, we report stochastic comparisons of maintenance policies for minimal repairs with the generalized age replacement. Results of comparisons of the same policy for different units with minimal repair in the hazard rate order are given.
In this paper, an integrated methodology is developed for optimizing inspection and maintenance of a component where delayed repair is considered to be one of feasible options. The models of failures, risk and life cycle cost are developed using probability, stochastic process and the delay time concept. The model is intended to optimise the inspection intervals and the delay of repair simultaneously...
According to analysis results of the failure modes of side-abrasion of rod strings for water-flood pump wells and the application of probability statistical and reliability theory, this paper properly treated and selected the failure data, and deduced the lifetime statistical model, realized qualitative analysis and quantitative evaluation for the working reliability. Through building the side-abrasion...
High density probe-based storage devices use multiple, simultaneously accessed parallel channels for achieving high I/O data rates. This paper presents an analytical methodology for evaluating the performance of coding and interleaving schemes in such devices, when they are affected by burst errors. Markov processes are used to describe the burstiness of errors due to external disturbances and analytical...
In this work, a method for determining the reliability of dynamic systems is discussed. Using statistical information on system parameters, the goal is to determine the probability of a dynamic system achieving or not achieving frequency domain performance specifications such as low frequency tracking error, and bandwidth. An example system is considered with closed loop control. A performance specification...
A conceptual possibility-probability based framework is proposed to manage the uncertainties encountered in distribution system reliability. Probability distribution of reliability parameters, the failure rate, the load point outage duration and the power injection of feeder branch are transformed consistently into the corresponding possibilistic distribution function. Under the proposed framework,...
Service level agreements (SLAs) are facilitators for widening the commercial uptake of grid technology. They provide explicit statements of expectation and obligation between service consumers and providers. However, without the ability to assess the probability that an SLA might fail, commercial uptake will be restricted, since neither party will be willing to agree. Therefore, risk assessment mechanisms...
Complex scientific workflows are now Increasingly executed on computational grids. In addition to the challenges of managing and scheduling these workflows, reliability challenges arise because of the unreliable nature of large-scale grid infrastructure. Fault tolerance mechanisms like over-provisioning and checkpoint-recovery are used in current grid application management systems to address these...
Cognitive radios (CRs) improve spectral efficiency by transmitting unlicensed signals over licensed frequency bands. A key requirement for CRs is to limit the interference to the licensed system. However, the variability in the radio channel caused by fading and shadowing makes this task more difficult. In this paper the performance of the licensed system has been analysed by calculating the probability...
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