Redundant Maintenance Research Articles

Intelligent Maintenance Prioritization and Optimization Strategies for Thermal Power Plant Boilers

Steam boiler also known as steam generator is an integral component in thermal power plants requiring effective maintenance scheduling to extend the overall life cycle of the boiler. However, steam boilers are commonly plagued with issues such as boiler shutdown and tube leakage. Industry experts adopted preventative maintenance to overcome the repetition of outage in steam boilers. This method is flawed in the aspect of redundant maintenance activities. The repetition in maintenance activities will lead to reduced work productivity and increased maintenance operational costs. In this study, a maintenance optimization system specialized in ranking, prioritization and optimization based on Analytical Hierarchy Process (AHP) and Particle Swarm Optimization (PSO) are chosen. The AHP is used to rearrange the maintenance activities according to its priority while the PSO is an intelligent swarm used to optimize the operational duration and maintenance cost based on the result formed from AHP after implemented using MATLAB software. This work proposes maintenance scheduling based on minimization of the objectives focusing on the forming new list of the maintenance activities with the optimal operational duration and maintenance cost.

Manufacturing-error-based maintenance for high-precision machine tools

Nowadays, the condition-based maintenance (CBM), in which repairs are triggered by the heuristic symptoms of the component faults, is finding increasing applications in the industrial fields. However, for the high-precision machine tools, the conventional CBM might not be the optimal option, which is uneconomic and incapable of ensuring their machining accuracy. In order to overcome these shortcomings, this paper propose the manufacturing-error-based maintenance (MEBM), where the repairs are initiated based on the manufacturing errors instead of the heuristic symptoms. In MEBM, repairs are taken properly at the occurrence of the excessive machining errors, and therefore, the premature and redundant maintenance can be avoided and the maintenance cost can be minimized; what is more, the machining errors are controlled in the closed loops, and therefore, the machining accuracy can be guaranteed. Based on the principles of the MEBM, a prototype maintenance system—the transient backlash error (TBE)-based maintenance system—is established. To achieve this aim, first, the width of the backlash in the mechanical chain is measured by utilizing the built-in encoders and the analytical mapping relationship between the backlash width and the TBE is derived. Relying on these foundations, the TBE can be indirectly estimated. Then, the warning threshold of the TBE is customized according to the permissible roundness error of the workpiece. Thus, the maintenance actions can be precisely implemented: when the monitored TBE exceeds its warning threshold, maintenance workers will be notified to lessen the backlash width, and meanwhile, the permissible maximal size for the backlash will also be informed.

MPJ Express Meets YARN: Towards Java HPC on Hadoop Systems

Many organizations—including academic, research, commercial institutions—have invested heavily in setting up High Performance Computing (HPC) facilities for running computational science applications. On the other hand, the Apache Hadoop software—after emerging in 2005— has become a popular, reliable, and scalable open-source framework for processing large-scale data (Big Data). Realizing the importance and significance of Big Data, an increasing number of organizations are investing in relatively cheaper Hadoop clusters for executing their mission critical data processing applications. An issue here is that system administrators at these sites might have to maintain two parallel facilities for running HPC and Hadoop computations. This, of course, is not ideal due to redundant maintenance work and poor economics. This paper attempts to bridge this gap by allowing HPC and Hadoop jobs to co-exist on a single hardware facility. We achieve this goal by exploiting YARN—Hadoop v2.0—that de-couples the computational and resource scheduling part of the Hadoop framework from HDFS. In this context, we have developed a YARN-based reference runtime system for the MPJ Express software that allows executing parallel MPI-like Java applications on Hadoop clusters. The main contribution of this paper is provide Big Data community access to MPI-like programming using MPJ Express. As an aside, this work allows parallel Java applications to perform computations on data stored in Hadoop Distributed File System (HDFS).

The KBART’s Potential beyond OpenURL Linking

Knowledge Base and Related Tools (KBART), initially founded with a focus on improving OpenURL linking through the definition of best practices for exchanging title-level metadata, continues to gain traction and has the potential to be an initiative that improves not only link resolver quality but also improves discovery services, electronic resource management (ERM) systems, and even Counting Online Usage of Networked Electronic Resources (COUNTER) usage reports. In this column we quickly review the history of KBART from its inception in 2007 through the creation of the Phase 1 and Phase 2 best practices. Then we investigate how KBART can positively influence the quality of discovery services, ERM systems, and COUNTER. Finally, we put forward some suggestions on how KBART can become the key to standardizing the exchange of holdings data within the information supply chain to address needs beyond link resolvers and eliminate some redundant holdings maintenance tasks in libraries.

Maintenance of cooperative overlays in multi‐overlay networks

In overlay-based applications, multiple overlay networks are deployed to fulfill different service requirements. A multi-overlay environment may exist in which a number of nodes simultaneously participate in the networks. When there are multiple overlay-based applications running over a set of nodes, some of the nodes take extra effort to maintain multi-overlay networks. Therefore, maintaining these co-existing overlays incurs redundant maintenance overhead. This research presents a cooperative strategy for exploiting a master–slave model to handle the common overlay-maintenance. The purpose is to eliminate the redundant maintenance overhead. To evaluate system performance, this study not only analyses various combinations of multiple overlays but also considers the effectiveness of the master selection approach. Experimental results demonstrated that the proposed cooperative strategy significantly decreases the redundant overlay-maintenance overhead. In some cases, the overall reduction ratio of maintaining multiple overlays is as high as 60%.

Preventive Maintenance Model Analysis Based on Condition

To improve operation maintenance management levels and increase economic profits for repairable devices, condition based preventive maintenance (CBM) has been widely applied in industrial enterprises in recent years. Compared with traditional time based maintenance (TBM), CBM not only can ensure the production process more safety but also dramatically reduce the examining-maintenance cost, which can be thought as a proactive maintenance scheme, practically. In this paper, we firstly construct the full life cycle model with four-state of the devices, and then simplified it into three-state model based on some practical considerations. On the basis of it, the paper analyzes its reliability operation characteristics under diverse maintenance models such as the proactive maintenance based on CBM, and the proactive maintenance based on TBM, and the passive maintenance, and the redundant maintenance scheme, and computes its desired maintenance cost and the investment payback period. The computing results show that the investments payback period is the shortest of the proactive maintenance rule based on CBM, and the one based on TBM comes second, and the one based on passive maintenance comes third, and the one of the redundant management model is the inferior. The investigations show that proactive maintenance based on CBM is a very effective operation maintenance management mode for repairable devices, and possesses very broad applications prosperity.

A preventive maintenance policy for a standby system subject to internal failures and external shocks with loss of units

In many situations, serious damage and considerable financial losses are caused by non-repairable failures of a system. Redundant systems and maintenance policies are commonly employed to improve reliability. This paper is focused on the modelling of a complex cold standby system by analysing the effectiveness and costs of preventive maintenance, always in an algorithmic form. The online unit of the system is subject to wear failures and external shocks. The online unit can go through an indeterminate number of degradation levels before failure. This one is observed when inspections occur. Inspections are performed at random intervals, and when one takes place, the unit is taken to the preventive maintenance facility if it is necessary. The preventive maintenance time and cost is different depending on the degradation level observed. If only one unit is performing, a minimal maintenance policy is adopted in order to optimise system behaviour. Reliability measures such as the conditional probability of failure are worked out in a well-structured and algebraic form in transient and stationary regimes by using algorithmic methods. The stationary distribution is calculated using matrix analytic methods, and rewards are included in the model. An optimisation example shows the versatility of the model presented.

Linking Data and Publications: Towards a Cross-Disciplinary Approach

In this paper, we tackle the challenge of linking scholarly information in multi-disciplinary research infrastructures. There is a trend towards linking publications with research data and other information, but, as it is still emerging, this is handled differently by various initiatives and disciplines. For OpenAIRE, a European cross-disciplinary publication infrastructure, this poses the challenge of supporting these heterogeneous practices. Hence, OpenAIRE wants to contribute to the development of a common approach for discipline-independent linking practices between publications, data, project information and researchers. To this end, we constructed two demonstrators to identify commonalities and differences. The results show the importance of stable and unique identifiers, and support a ‘by reference’ approach of interlinking research results. This approach allows discipline-specific research information to be managed independently in distributed systems and avoids redundant maintenance. Furthermore, it allows these disciplinary systems to manage the specialized structures of their contents themselves.

SOMS: A Subway Operation and Maintenance System Based on Planned Maintenance Model with Train State

This paper aims to propose a modeling framework for subway operation and maintenance system (SOMS), which analyzes the train condition data based on both train sensor network data and basis train maintenance plan. The system is formulated into five function modules, and the research problem is to determine one auxiliary maintains plan, including the time allocation and frequency of maintenance. The case of Guangzhou metro is conducted to illustrate the applicability of SOMS, and the results reveal a number of interesting insights into subway maintenance system, i.e., the worksheet can reduce duplication of redundant maintenance work, the repair cost, and the damage caused by frequent disassembly.

Roles of the checkpoint sensor clamp Rad9-Rad1-Hus1 (911)-complex and the clamp loaders Rad17-RFC and Ctf18-RFC in Schizosaccharomyces pombe telomere maintenance

While telomeres must provide mechanisms to prevent DNA repair and DNA damage checkpoint factors from fusing chromosome ends and causing permanent cell cycle arrest, these factors associate with functional telomeres and play critical roles in the maintenance of telomeres. Previous studies have established that Tel1 (ATM) and Rad3 (ATR) kinases play redundant but essential roles for telomere maintenance in fission yeast. In addition, the Rad9-Rad1-Hus1 (911) and Rad17-RFC complexes work downstream of Rad3 (ATR) in fission yeast telomere maintenance. Here, we investigated how 911, Rad17-RFC and another RFC-like complex Ctf18-RFC contribute to telomere maintenance in fission yeast cells lacking Tel1 and carrying a novel hypomorphic allele of rad3 (DBD-rad3), generated by the fusion between the DNA binding domain (DBD) of the fission yeast telomere capping protein Pot1 and Rad3. Our investigations have uncovered a surprising redundancy for Rad9 and Hus1 in allowing Rad1 to contribute to telomere maintenance in DBD-rad3 tel1 cells. In addition, we found that Rad17-RFC and Ctf18-RFC carry out redundant telomere maintenance functions in DBD-rad3 tel1 cells. Since checkpoint sensor proteins are highly conserved, genetic redundancies uncovered here may be relevant to telomere maintenance and detection of DNA damage in other eukaryotes.

Self-Organizing Map and Multi-Layer Perceptron Neural Network Based Data Mining to Envisage Agriculture Cultivation

Study on characteristics of soil, to determine the types of crops suitable for cultivation in a particular region can increase the yield to greater extent, which minimizes the expenditures involved in irrigation and application of fertilizers. With the tested techniques available for calibrating the quality of soil and the crops suitable for cultivation in it, it is possible to determine the exact crop, irrigation patterns and even the cycle and quantity of fertilizer application. This paper dealt with the application of SOM based clustering and Artificial Intelligence techniques, to analyze the patterns of soils distributed across huge geographical area and identify the suitable types of crops for the particular soil. Estimation of exact crop(s) suitable for a particular region can help stave off redundant maintenance and the inherent expenditures that would occur due to over irrigation and over usage of fertilizers, to fulfill the natural deficiencies. Our Focus is to improve the optimal utilization of innate characteristics in a soil through cultivation of appropriate crops, which will increase the volume and quality of yield, in particular for a developing country like India, where the huge majority of the population depends primarily on agriculture for livelihood.

Reliability analysis of triple modular computer systems with redundant voters and restricted maintenance

Presents five newly developed models for a Triple Modular Redundancy system having zero, one, two, three, and N voters. Expressions for reliabilities and mean time to failure with and without repair are developed. The plots for state probabilities, reliabilities and mean time to failure are shown.

Reliability of a Repairable System with Redundant Units and Preventive Maintenance

The lifetime distribution of a repairable system with redundant units and preventive maintenance is considered. This distribution is used to compute the s-expected time to system failure and steady-state availability.