Explore the vast range of titles available.

The article presents issues regarding the impact of operating conditions on the functional reliability of representative fire alarm systems (FASs) in selected critical infrastructure buildings (CIB). FAS should operate correctly under variable environmental conditions. FASs ensure the safety of people and CIB. Operational measurements for 10 representative systems were conducted in order to determine the impact of environmental conditions on FAS reliability. Selected operational indices were also determined. The next stage involved developing two models of representative FASs and the availability, pre-ageing time and operating process security indices. Determining operational indices is a rational selection of FAS technical and organizational solutions that enables the reliability level to be increased. Identifying the course of the FAS operating process security hazard changes in individual system lines, particularly at the initial operation stage, enables people that supervise the operation to affect operating parameters on an ongoing basis. The article is structured in the following order: issue analysis, FAS power supply in CIB, operational test results, selected FAS operating process models, determination of operational and security indices, and conclusions.

Balancing markets (BMs) play a crucial role in ensuring the real-time equilibrium between electricity demand and supply. The current requirements for participation in BMs often overlook the characteristics and capabilities of variable renewables, limiting their effective integration. The increasing penetration of variable renewables necessitates adjustments in the design of BMs to support the transition toward carbon-neutral power systems. This study examines the levels of active market participation for a wind power producer (WPP) in the Iberian Electricity Market and the Portuguese BMs. In addition to exploring current market dynamics, the study tests one methodology proposed by the Danish Transmission System Operator to support the participation of variable renewables in BMs, the P90, and two new methods based on the full cost balancing concept. These methodologies incentivize WPPs to minimize imbalances by allowing market participation only if imbalances remain within a 10% deadband of annual hours (P90), hourly offers (D90), or both (DP90). The results indicate that participating in the secondary capacity market, particularly for downward capacity, is the most profitable strategy. This participation enhances the value of wind power by over 42%. However, in most methodologies, the WPP failed to deliver nearly 100% of its allocated capacity approximately 1% of the time. In contrast, the D90 approach limited the maximum deviation to 10%, demonstrating the highest reliability among the evaluated methods.

System integrity protection schemes (SIPS) are a widely used solution to the challenges in operating electrical power transmission systems during the last few decades. Since these protection schemes have become an integral part of the system, it must be ensured that their performance satisfies the reliability requirements of electrical utilities, when expressed in terms of dependability and security. This study proposes a method based on Markov modelling and fault tree analysis for assessing the reliability of a generic SIPS, but it is illustrated using the Dinorwig intertrip scheme, located in North Wales and operated by National Grid (Great Britain system operator). In addition, two reliability indices, widely used in the process control industry, are suggested for quantifying the reliability level of SIPS: (i) safety integrity level and (ii) spurious trip level. Many operators tend to have SIPS permanently in service; this reduces the probability of a ‘failure to operate’ because of a problem in the arming software or an error by a human operator that prevented the scheme being armed when required. Therefore, the impact of having SIPS always armed on SIPS reliability is compared with the impact of switching IN the scheme only when the arming conditions are fulfilled.

Capacity markets (CMs) have been widely analysed and implemented in various regions to enhance the capacity adequacy and supply security in power systems with high renewable penetration. This study compares the performance of two market designs, an energy market combined with a CM and an energy‐only market, using a capacity expansion model that incorporates long‐term energy storage (ES). This study contributes significantly to the debate on CM by quantifying the improvement in the system reliability. Through simulations conducted on provincial power systems in China, we demonstrate that introducing a CM significantly enhances the system reliability by providing a stable revenue stream that incentivises capacity investments. Additionally, the effectiveness of implementing a CM is analysed through simulations under various market conditions, thereby presenting various advantages. Furthermore, the results of this study indicate that the reliable availability of conventional technologies is essential for future power systems with high renewable energy penetration. The supply security cannot be ensured with an excessive penetration level of renewable energy sources, despite long‐term ES. These findings present critical insights into the design of hybrid electricity markets for transitioning power systems.

The paper deals with the possibilities of allocating reliability requirements for a system using complex redundancy. It means system consists of a few identical subsystems and for its common function it is quite enough if only certain part of these subsystems operates. The subsystems not operating at a certain moment serve as redundancy in case that the subsystems which are operating fail. All the system, however, is not a trivial parallel structure, because if the system is to work properly, always more than one subsystem should operate and the subsystems can function only in configurations set in advance. Practical application of the suggested method of reliability allocation is demonstrated for a pantograph system of a high-speed train. In order to provide the proper function of the system, the minimum number of operating pantographs in pre-set configurations providing safe current collection has to be always available. Using some pantograph configurations (e.g. two pantographs being one after another very closely) is in fact not possible for safety reasons. The article presents the procedure of reliability allocation for this specific system. Suggested method is based on a truth table and Boolean algebra application.

Product development begins with the concept phase. It consists of two parts, the product concept and design concept. In the concept phase, a decision is made to develop a new product. It is in the concept phase that the product is defined on the basis of market needs, customer focus, product features, product cost, business fit, and product architecture. This chapter presents a summary list of the reliability activities performed in the product concept phase along with the expected deliverables. There are five major reliability activities that take place in the product concept phase. These include establishing the reliability organization, defining the reliability process, defining product reliability requirements, capturing and applying lessons learned, and mitigating risk. An integral reliability activity in the product concept phase is setting the product reliability requirement. The risk mitigation meeting requires sign‐off on every risk issue.

This chapter contains sections titled: On time and reliability On spacecraft and reliability: early studies Book organization

Once reliability requirements have been established and a system has been developed and deployed, important information can be gained from determining whether the requirements are being met. This chapter deals with some ideas for a failure reporting analysis and corrective action system (FRACAS) that systematizes the process of data collection, archiving, and analysis for more effective and efficient feedback about the reliability of deployed systems. Reliability testing is the source of a great many interesting problems in test design, data collection, and analysis. The most prominent types of reliability testing include component life testing, reliability growth testing and software reliability testing. The chapter describes some tools that help make appropriate comparisons between reliability requirements and reliability performance, reliability performance and reliability modeling and reliability modeling and reliability requirements.

The increasing complexity of systems poses a big challenge to design systems with fault-tolerant capability. The aim of this study was to establish fault-tolerant system for multiprocessor platform with the help of hierarchical scheduling framework. A mathematical fault and reliability model for hierarchical scheduling framework was proposed firstly, and then a heuristic algorithm by exploiting the difference of task resource overhead and the probability of task failures was presented and a task replication scheme was given lastly. The experimental results demonstrated the proposed scheme could effectively guarantee reliability goal and reduce resource consumption simultaneously.