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This study aims to obtained the failure probability distributions of subsystems for industrial robot and filtrate its fault data considering the complicated influencing factors of failure rate for industrial robot and numerous epistemic uncertainties.

A fault data screening method and failure rate prediction framework are proposed to investigate industrial robot. First, the failure rate model of the industrial robot with different subsystems is established and then the surrogate model is used to fit bathtub curve of the original industrial robot to obtain the early fault time point. Furthermore, the distribution parameters of the original industrial robot are solved by maximum-likelihood function. Second, the influencing factors of the new industrial robot are quantified, and the epistemic uncertainties are refined using interval analytic hierarchy process method to obtain the correction coefficient of the failure rate.

The failure rate and mean time between failure (MTBF) of predicted new industrial robot are obtained, and the MTBF of predicted new industrial robot is improved compared with that of the original industrial robot.

Failure data of industrial robots is the basis of this prediction method, but it cannot be used for new or similar products, which is the limitation of this method. At the same time, based on the series characteristics of the industrial robot, it is not suitable for parallel or series-parallel systems.

This investigation has important guiding significance to maintenance strategy and spare parts quantity of industrial robot. In addition, this study is of great help to engineers and of great significance to increase the service life and reliability of industrial robots.

This investigation can improve MTBF and extend the service life of industrial robots; furthermore, this method can be applied to predict other mechanical products.

This method can complete the process of fitting, screening and refitting the fault data of the industrial robot, which provides a theoretic basis for reliability growth of the predicted new industrial robot. This investigation has significance to maintenance strategy and spare parts quantity of the industrial robot. Moreover, this method can also be applied to the prediction of other mechanical products.

Market demands, especially within the automotive sector, are pushing towards increased product complexity and performance with zero ship parts per million (PPM) requirements. To achieve both quality and performance goals very stringent requirements are being placed on the test manufacturing solution. These requirements lead to conflicts between cost, performance and quality. The purpose of this paper is twofold: first, to investigate the conflicts that exist between quality, performance, and cost, and second, to review current practices and techniques being used in tests to minimise ship PPM.

In the paper a test process development flow chart is presented, along with a review of current methods being used for both defect screening and performance testing. The relationship between test coverage and ship PPM is investigated using established yield models. The cost in terms of gross margin degradation of yield loss at final test to extensive screening and aggressive limits is modelled.

The paper finds that to maintain ship PPM very high levels of test coverage are required – typically test coverage needs to be > 98 per cent. The cost of yield loss to this testing typically matches on a percentage point basis gross margin degradation. Reviewing current test methods shows the need both for extensive defect‐screening techniques for the defective portion of the population, and for optimised guardbanding techniques for performance testing. Weaknesses that exist are the absence of a model to predict outgoing PPM, and the conservative nature of existing guardband techniques for performance testing.

This is a review paper and it serves to highlight both the weaknesses in current practices, and areas where improved models are required.

Seismic vulnerability evaluation of various public structures, especially school buildings, is very crucial for designing hazard mitigation initiatives in seismic prone areas. The city of Mymensingh is at great risk of earthquake because of its geographical location, geological structure and proximity to active faults. The city is famous for its ancient and renowned educational institutes that need to be evaluated for understanding the seismic performance of the building during an earthquake. This study aims to evaluate the seismic vulnerability of educational buildings of Mymensingh city using rapid visual screening (RVS) and index based approach.

RVS procedure includes field survey and secondary source assessment for evaluating structural vulnerability attributes. Analytical hierarchy process is applied to develop an index focusing on systematic attributes of vulnerability based on expert opinions. Then, a composite vulnerability map is developed combining both structural and systematic vulnerability score providing an equal weight.

This study evaluates the seismic vulnerability of 458 educational buildings of Mymensingh city and the result shows that 23.14% educational building has high, 46.29% has moderate and 26.86% has moderately low and only 3.71% buildings has the low seismic vulnerability. This study expected to be helpful in resource targeting and prioritizing seismic hazard mitigation activities for education buildings of Mymensingh city.

This study endeavors to present a comprehensive vulnerability assessment method by integrating RVS and index based approach that incorporates both structural and systematic dimensions of vulnerability. The result is expected to be helpful in the formulation of disaster prevention policy for vulnerable educational buildings and development of the earthquake-resistant building codes for the new building construction in Mymensingh city.

Whereas a human operator is hard to observe the networking infrastructure and its functions on a continuous basis, wireless sensor network (WSN) nodes must overcome faults and route the perceived data to the sink/base stations (BS). The main target of this research article is to ensure the fault-tolerance (FT) capability, especially for transmission of sensed data to its destination without failure. Thus, through this paper, a fuzzy-based subordinate support (FSS) system is introduced as an additional feature to the existing optimized mobile sink improved energy efficient Power-Efficient Gathering in Sensor Information Systems (PEGASIS)-based (OMIEEPB) routing protocol, which lacks focus on ensuring the FT capabilities to the selected leaders of the corresponding chain. The central focus of FSS is to prevent the incident of fault, especially to the cluster heads.

WSNs encounter several issues owing to random events or different causes such as energy exhaustion, negative influences of the deployed region, signal interference, unbalanced supply routes, instability of motes due to misalignments and collision, which ultimately intends the failure of the network. Throughout the past investigation periods, researchers gain an understanding of fault-tolerant strategies that may improve the data integrity or reliability, precision, energy efficiency, the life expectancy of the system and reduce/prevent the failure of deployed components. If that is the case, the maximum chances of data packets (sensed) needed to be transferred reliably and accurately to the sink node or BS are degraded.

The FSS system utilizes the fuzzy logic concepts that have been proved to be beneficial since it permits several parameters to be combined effectively and evaluated. Here, near-point, residual energy, total operation time and past average processing time are considered as vital parameters. Moreover, the FSS system ensures the key performance activities of the network, such as optimization of response time, enhancing the data transmission reliability and accuracy. Simulation-based experiments are carried out through the Mannasim framework. After several experimental executions, the outcome of the proposed system is analyzed through elaborated comparison with the advanced existing systems.

Finally, it has been observed that the FSS system not only enhanced the FT features to OMIEEPB but also assures the improved accuracy level (>95%) with optimized response time (<0.09 s) during data communication between leaders and the normal nodes.

The paper proposes to present the effect of the high voltage transmission lines on the metallic pipelines by calculating the induced voltage due to mutual inductance between the two circuits especially in short circuit conditions of high voltage overhead transmission lines.

The electro magnetic transient program (EMTP) is used to simulate the high voltage transmission lines in normal case and in different faulty case conditions. A software is built on MATLAB program (M‐file) to study the effects of various parameters on the magnitude of the induced voltage such as: separation distance between the high voltage transmission line and the metallic pipeline (horizontal distance), different cases of short circuits and normal operation case, the screening factor, and the soil resistivity.

The three‐phase to ground fault gives the least induced voltage, and phase to ground fault case is the most serious case. The induced voltage decreases with increasing the soil resistivity until 400 Ωm and after this, the induced voltage in the metallic pipeline increases with increasing the soil resistivity for all phase fault types.

It does not deal with all types of interference such as capacitive interference.

This technique helps to know the electrical influence exerted by power line on a pipeline. So it can prevent the pipeline from posing a shock hazard rather than corrosion.

This paper presents the effect of the high voltage transmission lines on the metallic pipelines by calculating the induced voltage due to mutual inductance between the two circuits especially in short circuit conditions of high voltage overhead transmission lines.

Research questions: Is there a systemic relationship between different methods of screening candidates for predictive maintenance? How do the goals of a predictive project influence the choice of a dropout method? How do the company’s characteristics implementing the predictive project influence the selection of the dropout method?

The authors described and compiled a taxonomy of currently known methods of screening candidate aircraft components for predictive maintenance for maintenance, repairs and overhaul organizations; identified the boundaries of each way; analyzed the advantages and disadvantages of existing methods; and formulated directions for further development of methods of screening for maintenance, repairs and overhaul organizations.

The authors identified the relationship between various screening methods by developing the approach proposed by Tiddens WW and supplementing it with economic methods. The authors built them into a single hierarchical structure and linked them with the parameters of the predictive project. The principal advantage of the proposed taxonomy is a clear relationship between the structure of the screening methods and the goals of the predictive project and the characteristics of the company that implements the project.

The authors of the article proposed groups of screening methods for predictive maintenance based on economic indicators to improve the effectiveness and efficiency of the screening process.

Intrusions exploit vulnerabilities and introduce external disturbances into information systems to compromise security attributes of information systems such as availability, integrity, and confidentiality. Intrusions into information systems cause faults of software and hardware components in information systems, which then lead to errors and failures of system performance. Intrusion tolerance requires information systems to function correctly in a timely manner even under impact of intrusions. In this paper, we discuss causes, chain effects and barriers of intrusions into information systems, and reveal roles that various information security techniques play in intrusion tolerance. We present two robust intrusion tolerance methods through fault masking: Taguchi’s robust method for system configuration and sharing of resources via an information infrastructure for redundancy.

The purpose of this study is to detect and reconstruct a fault in pitot probe and static ports, which are components of the air data system in commercial aircrafts, without false alarm and no need for pitot-static measurements. In this way, flight crew will be prevented from flying according to incorrect data and aircraft accidents that may occur will be prevented.

Real flight data collected from a local airline was used to design the relevant system. Correlation analysis was performed to select the data related to the airspeed and altitude. Fault detection and reconstruction were carried out by using adaptive neural fuzzy inference system and artificial neural networks, which are machine learning methods. MATLAB software was used for all the calculations.

No false alarm was detected when the fault test following the fault modeling was carried out at 0–2 s range by filtering the residual signal. When the fault was detected, fault reconstruction process was initiated so that system output could be achieved according to estimated sensor data.

The presented alternative analytical redundant airspeed and altitude calculation scheme could be used when the pitot-static system contains any fault condition.

Instead of using the methods based on hardware redundancy, the authors designed a new system within the scope of this study. Fault situations that may occur in pitot probes and static ports are modeled and different fault scenarios that can be encountered in all flight phases have been examined.

First contract arbitration (FCA) provisions are posed as a solution to the difficulties of negotiating a first contract for newly certified bargaining units. FCA is a longstanding, and no longer controversial, element of Canadian labor legislation. FCA provisions now exist in six Canadian jurisdictions and four distinct FCA models have developed (the exceptional remedy or fault model, the automatic access model, the no-fault model, and the mediation intensive model). In the United States the Employee Free Choice Act (EFCA) included a highly contested proposal to amend the National Labor Relations Act (NLRA) to include an FCA provision similar to the Canadian automatic access model. This chapter offers a balanced assessment of FCA evidence from Canada addressing the main objections to FCA in the EFCA debates. Individual case level data from jurisdictions representing each of the four FCA models is examined. The evidence demonstrates that although FCA is widely available in Canada, it is an option that is rarely sought and, when sought, rarely granted; that parties involved in FCA are able to establish stable bargaining relationships; and, that this process does not, as critics charge, simply prolong the life of nonviable bargaining units. This chapter concludes by suggesting that the practice under Quebec's “no-fault” model and British Columbia's “mediation intensive” model merit consideration for adoption elsewhere. These models position the FCA process as a mechanism fostering collective bargaining and voluntary agreements, rather than treating it as a remedy for dysfunctional negotiations and as part of the unfair labor practice framework.

This paper seeks to propose a methodology based on Petri nets to evaluate the reliability parameters of a screening system in paper industry. The effects of failures and courses of action on the system performance have also been investigated.

Generalized stochastic Petri nets (GSPN), a class of Petri nets, has been used to model the interactions amongst the active/standby units of the system; and Markovian approach has been used to evaluate the reliability parameters. The data related to equipments' operational behavior were collected, processed and quantified. Using the data, reliability analysis of system in the long run conditions has been carried out. The sensitivity analysis has been performed to study the effect of failure/repair rates of each unit of the system on system performance.

The methodology adopted in this paper provides a better understanding on the behavior of the system through its graphical representation. The reachability graph generated with Petri net model helps to identify the state space evolution of the system.

Reliability analysis of a screening system of the paper industry presented in this paper will help management in deciding upon the maintenance strategy to be adopted with the objective of improving the performance of the system and consequently reducing the operational and maintenance costs.