Relevant bibliographies by topics / Repair And Maintenance Of Specific Models

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  1. Journal articles
  2. Dissertations / Theses
  3. Books
  4. Book chapters
  5. Conference papers
  6. Reports

Academic literature on the topic 'Repair And Maintenance Of Specific Models'

Author: Grafiati
Published: 4 June 2021
Last updated: 12 February 2022

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Journal articles on the topic "Repair And Maintenance Of Specific Models"

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Golovin, Sergey. "Representation of replacement rules in the form of a matrix." Journal of Quality in Maintenance Engineering 22, no. 2 (May 9, 2016): 164–79. http://dx.doi.org/10.1108/jqme-06-2015-0022.

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Purpose – The purpose of this paper is to represent replacement policies (rules) in the form of a matrix. Visualization of replacement rules is useful for maintenance records. Matrix representation is more effective than the verbal description usually provided, as it allows better understanding of the specifics of the different replacement rules without careful research of their mathematical models. Design/methodology/approach – This approach employs mathematical models to investigate the simple conditions (requirements) for replacement of system component with illustrative examples. When comparing the different replacement rules a cost structure is applied to takes into account the nature and technology of disassembly assembly actions for the repair unit. Findings – Representation of replacement rules in the matrix form is useful when describing planned replacement models, opportunity replacement models, group replacement models and others, as well as computer modeling of the renewal process. Forming simple conditions for the replacement of system components ensures the total average repair cost is minimized. These conditions can be applied in the early stages of creating a maintenance program for the machine. Practical implications – Replacement matrices can be specified in a technical manual for maintenance of machines to achieve reliable operation and to reduce repair costs. Replacement matrices can be put into practical use for maintenance records and may be included in the maintenance procedures library of CMMSs. Developed in the paper, the replacement matrix, the conditions for replacement of system components and the cost structure will help engineers to make decisions at the time of repair for assembly units. Originality/value – Proposed in the paper is a new approach to the visualization of the replacement rules and cost structure which simplifies the analysis of options for repair actions. The proposed technique contributes to the record of maintenance actions and the decision making process for replacement.
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Cardeal, Gonçalo, Kristina Höse, Inês Ribeiro, and Uwe Götze. "Sustainable Business Models–Canvas for Sustainability, Evaluation Method, and Their Application to Additive Manufacturing in Aircraft Maintenance." Sustainability 12, no. 21 (November 3, 2020): 9130. http://dx.doi.org/10.3390/su12219130.

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The topic of sustainable business models is growing in literature and in the industry, driving companies to search for opportunities to improve their impact on the three pillars of sustainability—profit, people, and planet (economic, social, and environmental). However, the process of developing sustainable business models is often complex, due to conflicting objectives from the three dimensions of sustainability. This paper presents a procedure model that supports the design and assessment of business models with a sustainable perspective, by integrating a new business model canvas for sustainability (BMCS) and an evaluation method to assess it. A comprehensive assessment is proposed, performed in a life cycle perspective. The proposed model is applied and validated with a real case study, based on a new business model for an aircraft maintenance, repair, and overhaul company. The case is based on shifting from traditional maintenance, repair, and overhaul activities to adopting additive manufacturing as an activity that allows manufacturing optimized spare parts with benefits for the costumer. The results show the application of the procedure model on a specific case study, as well as the potential of additive manufacturing as a driver for more sustainable business models in the aircraft maintenance sector.
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Capodieci, Antonio, Antonio Caricato, Antonio Paolo Carlucci, Antonio Ficarella, Luca Mainetti, and Cristian Vergallo. "Using different machine learning approaches to evaluate performance on spare parts request for aircraft engines." E3S Web of Conferences 197 (2020): 11014. http://dx.doi.org/10.1051/e3sconf/202019711014.

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The Aircraft uptime is getting increasingly important as the transport solutions become more complex and the transport industry seeks new ways of being competitive. To reach this objective, traditional Fleet Management systems are gradually extended with new features to improve reliability and then provide better maintenance planning. Main goal of this work is the development of iterative algorithms based on Artificial Intelligence to define the engine removal plan and its maintenance work, optimizing engine availability at the customer and maintenance costs, as well as obtaining a procurement plan of integrated parts with planning of interventions and implementation of a maintenance strategy. In order to reach this goal, Machine Learning has been applied on a workshop dataset with the aim to optimize warehouse spare parts number, costs and lead-time. This dataset consists of the repair history of a specific engine type, from several years and several fleets, and contains information like repair claim, engine working time, forensic evidences and general information about processed spare parts. Using these data as input, several Machine Learning models have been built in order to predict the repair state of each spare part for a better warehouse handling. A multi-label classification approach has been used in order to build and train, for each spare part, a Machine Learning model that predicts the part repair state as a multiclass classifier does. Mainly, each classifier is requested to predict the repair state (classified as “Efficient”, “Repaired” or “Replaced”) of the corresponding part, starting from two variables: the repairing claim and the engine working time. Then, global results have been evaluated using the Confusion Matrix, from which Accuracy, Precision, Recall and F1-Score metrics are retrieved, in order to analyse the cost of incorrect prediction. These metrics are calculated for each spare part related model on test sets and, then, a final single performance value is obtained by averaging results. In this way, three Machine Learning models (Naïve Bayes, Logistic Regression and Random Forest classifiers) are applied and results are compared. Naïve Bayes and Logistic Regression, that are fully probabilistic methods, have best global performances with an accuracy value of almost 80%, making the models being correct most of the times.
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Romanov, Vladimir S., and Valery G. Goldshtein. "To the question of damage, maintenance and repairs of submersible electric equipment for oil production." Vestnik of Samara State Technical University. Technical Sciences Series 28, no. 2 (July 27, 2020): 111–23. http://dx.doi.org/10.14498/tech.2020.2.8.

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In optimizing and managing the life cycles of submersible electrical equipment (SEE) for oil production, an integrated approach to the organization of maintenance and repairs (MRO) is advisable based on the development of a more advanced strategy for carrying out repair cycles. It is stated that the maintenance and repair strategies adopted by the oil industry do not fully ensure operational efficiency, which leads to an increase in premature equipment failures, a reduction in turnaround times and, as a result, losses for oil companies. The advantages and disadvantages of approaches to organizing the operation of SEE on the operating time and the actual state in the planning, implementation of maintenance and repair, as well as the feasibility of their complex application are evaluated. It is proposed to use statistical models to make an informed decision on determining the composition and period of MRO, forecasting the boundary states of sets in general and specific SEE electrical installations. At a given operating time, it is possible to determine the basic laws of the appearance of defects and the mean time between failures (MTBF) of the elements, as well as the fleet of equipment of oil-producing enterprises as a whole. The results obtained are the rationale for a set of recommendations to improve operational efficiency and optimize life cycle management of submersible electrical equipment for oil production.
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Islam, Md Shafiqul, Shayla Sharmin, and Jebunnesa Islam. "Multiple repair scenario of life cycle cost of RCC girder bridge using Markov chain model." Challenge Journal of Concrete Research Letters 10, no. 4 (December 21, 2019): 75. http://dx.doi.org/10.20528/cjcrl.2019.04.001.

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At present, many road authorities in the world face challenges in condition monitoring diagnosis of distress and forecasting deterioration, strengthening and convalescence of aging bridge structures. The accurate prediction of the future condition is crucial for optimizing the maintenance activities. It is very tough to predict the actual performance scenario or actual in–situ structures without carrying out inspection. Limited availability of detailed inspection data is considered as one of the major drawbacks in developing deterioration models. In State Based Markov deterioration (SNMD) modelling, the main job is to estimate transition probability matrixes (TPMs). In this paper, Markov Chain Monte Carlo (MCMC) is used to estimate TPMs. In Markov Chain Model, future conditions depend on only present bridge inspection data. Multiple repair options are adopted in order to optimize life cycle cost. Repairs are needed when the critical chloride concentration exceeds 0.2. Three distinct types of cost corresponding to each repair option is considered. The objective of this paper is to minimize the life cycle cost considering appropriate repair timings of mixed repair methods. Variation of life cycle cost of five different concretes (stronger to weaker) using three different repair option is shown in this paper. For specific normalized condition of concrete’s failure probability (0.3) and specific type of concrete, variation of life cycle cost using multiple repair options is also shown in this paper.
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Tomasova, Kristyna, Michal Kroupa, Asta Forsti, Pavel Vodicka, and Ludmila Vodickova. "Telomere maintenance in interplay with DNA repair in pathogenesis and treatment of colorectal cancer." Mutagenesis 35, no. 3 (February 21, 2020): 261–71. http://dx.doi.org/10.1093/mutage/geaa005.

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Abstract Colorectal cancer (CRC) continues to be one of the leading malignancies and causes of tumour-related deaths worldwide. Both impaired DNA repair mechanisms and disrupted telomere length homeostasis represent key culprits in CRC initiation, progression and prognosis. Mechanistically, altered DNA repair results in the accumulation of mutations in the genome and, ultimately, in genomic instability. DNA repair also determines the response to chemotherapeutics in CRC treatment, suggesting its utilisation in the prediction of therapy response and individual approach to patients. Telomere attrition resulting in replicative senescence, simultaneously by-passing cell cycle checkpoints, is a hallmark of malignant transformation of the cell. Telomerase is almost ubiquitous in advanced solid cancers, including CRC, and its expression is fundamental to cell immortalisation. Therefore, there is a persistent effort to develop therapeutics, which are telomerase-specific and gentle to non-malignant tissues. However, in practice, we are still at the level of clinical trials. The current state of knowledge and the route, which the research takes, gives us a positive perspective that the problem of molecular models of telomerase activation and telomere length stabilisation will finally be solved. We summarise the current literature herein, by pointing out the crosstalk between proteins involved in DNA repair and telomere length homeostasis in relation to CRC.
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Prizeman, Oriel. "Maintenance of shared spaces: courtyards of Tbilisi." Journal of Cultural Heritage Management and Sustainable Development 6, no. 3 (November 21, 2016): 316–29. http://dx.doi.org/10.1108/jchmsd-11-2015-0043.

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Purpose The courtyard dwellings of Tbilisi form a critical part of the city’s architectural identity. However, the multiple occupation of these buildings is blamed for confounding their prospects for repair and consequent valorisation as a World Heritage Site. Models for the shared ownership of residential blocks have been adapted globally. Some have established communal sources for rehabilitation and maintenance applicable to historic buildings. The purpose of this paper is to assess the relevance of such precedents to the complex and urgent context of Tbilisi’s threatened architectural heritage. Design/methodology/approach The paper uses existing literature and data to establish a hypothesis in support of adopting a collaborative approach for the maintenance and rehabilitation of shared buildings in a challenging and specific context. Using socio-economic data to characterise the occupants of such buildings and current critical sources, the paper investigates how existing collective communities can be empowered to capitalise from their unique social frameworks. Findings It finds evidence to support theoretical claims that there is scope for co-operative networks to flourish there. Research limitations/implications The paper is limited to a desktop analysis and relies upon available data and literature to draw its conclusions. Originality/value This paper addresses a critical problem in the formulation of conservation plans for Old Tbilisi, it tests the relevance of global exemplars for community repair programmes by reference to existing data for the care of the predominantly domestic architecture of Old Tbilisi at a time of rapid change.
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Ovchar, R. F. "Analysis of effectiveness of process operational and technological reliability of agricultural mashines." Naukovij žurnal «Tehnìka ta energetika» 11, no. 4 (September 10, 2020): 143–52. http://dx.doi.org/10.31548/machenergy2020.04.143.

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The analysis suggests that to solve the contradiction between the need of ensuring the required level of serviceability of combine harvesters and capabilities of existing system and repair management of the technical state of combine harvesters at the present stage, there is a need to improve the subsystem recovery combine harvesters subject to the requirements of readiness to perform tasks on purpose and financial capacity for its maintenance. Analysis of scientific literature showed that today the unsolved problem of search and introduction of effective methods and repair combine harvesters are: development of mathematical models of the process and repair, which would allow comparative assessment of technical and economic efficiency of different modes, and repair objects combine harvesters, alternative strategies for their repair, with the aim of improving the quality of control of technical condition of the vessel in conditions of limited funding. Consideration of the process of technical maintenance of combine harvesters as a set of stages and repair objects combine harvesters allows to identify possible directions of improving the system restore. The analysis allowed to determine four basic options for its organization and to make a qualitative assessment of the benefits and disadvantages of each of these options. Reduced operating costs in the operation of combine harvesters, along with other measures of organizational and technical nature require greater automation of control of technical condition. Automation of technical state control of combine harvesters developed in the following areas: embedded systems control, on-board automated control systems, specialized control systems and universal control systems dismantled equipment. A large share of false failures in equipment, violation of industrial relations in the repair network on-board equipment, the shortage of maintenance fund requires implementation and operation. Most fully able to examine the efficiency of the process of operation of complex technical systems using analytical models. Existing approaches to the assessment of the recovery system can be classified also according to the used indicators of effectiveness: the number of constructive variables of units that are replaced (restored) for a predetermined period of operation of the control object, repair cost of the constituent elements of the functional system for a specific period at different depths of the control and completeness of the recovery, the downtime of the test object within a certain period, for comprehensive reliability, such as coefficient of readiness, coefficient of technical use.
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Amadei, Bernard. "Agent-Based and System Dynamics Modeling of Water Field Services." Challenges 11, no. 2 (July 20, 2020): 13. http://dx.doi.org/10.3390/challe11020013.

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This paper explores the applicability of the agent-based (AB) and system dynamics (SD) methods to model a case study of the management of water field services. Water borehole sites are distributed over an area and serve the water needs of a population. The equipment at all borehole sites is managed by a single water utility that has adopted specific repair, replacement, and maintenance rules and policies. The water utility employs several service crews initially stationed at a single central location. The crews respond to specific operation and maintenance requests. Two software modeling tools (AnyLogic and STELLA) are used to explore the benefits and limitations of the AB and SD methods to simulate the dynamic being considered. The strength of the AB method resides in its ability to capture in a disaggregated way the mobility of the individual service crews and the performance of the equipment (working, repaired, replaced, or maintained) at each borehole site. The SD method cannot capture the service crew dynamics explicitly and can only model the average state of the equipment at the borehole sites. Their differences aside, both methods offer policymakers the opportunity to make strategic, tactical, and logistical decisions supported by integrated computational models.
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Ninou, Anna Huguet, Jemina Lehto, Dimitrios Chioureas, Hannah Stigsdotter, Korbinian Schelzig, Emma Åkerlund, Greta Gudoityte, et al. "PFKFB3 Inhibition Sensitizes DNA Crosslinking Chemotherapies by Suppressing Fanconi Anemia Repair." Cancers 13, no. 14 (July 18, 2021): 3604. http://dx.doi.org/10.3390/cancers13143604.

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Replicative repair of interstrand crosslinks (ICL) generated by platinum chemotherapeutics is orchestrated by the Fanconi anemia (FA) repair pathway to ensure resolution of stalled replication forks and the maintenance of genomic integrity. Here, we identify novel regulation of FA repair by the cancer-associated glycolytic enzyme PFKFB3 that has functional consequences for replication-associated ICL repair and cancer cell survival. Inhibition of PFKFB3 displays a cancer-specific synergy with platinum compounds in blocking cell viability and restores sensitivity in treatment-resistant models. Notably, the synergies are associated with DNA-damage-induced chromatin association of PFKFB3 upon cancer transformation, which further increases upon platinum resistance. FA pathway activation triggers the PFKFB3 assembly into nuclear foci in an ATR- and FANCM-dependent manner. Blocking PFKFB3 activity disrupts the assembly of key FA repair factors and consequently prevents fork restart. This results in an incapacity to replicate cells to progress through S-phase, an accumulation of DNA damage in replicating cells, and fork collapse. We further validate PFKFB3-dependent regulation of FA repair in ex vivo cultures from cancer patients. Collectively, targeting PFKFB3 opens up therapeutic possibilities to improve the efficacy of ICL-inducing cancer treatments.
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Dissertations / Theses on the topic "Repair And Maintenance Of Specific Models"

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Coxon, W. D. "Evaluation of models for decision making in inspection and repair maintenance." Master's thesis, University of Cape Town, 1987. http://hdl.handle.net/11427/21151.

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There has been growth in the costs of maintenance over the last 40 years. This can be linked directly to the changes in production technology over that period of time. However. there has also been growth in the field of management science and operations research. Many models have been developed to assist the maintenance function in its decisions. However. it would appear from engineering journals and shop floor practice that these models are not well used. For this research the method of inspection and repair maintenance has been chosen. Mainly because it is one of the most widely used methods. The objectives of the research are as follows: (1) To investigate the state of the art of plant and equipment maintenance paying particular attention to the inspection and repair policy. (2) To establish what basic models are available for decision making in inspection and repair maintenance. (3) To establish how feasible and useful each of these models is in the practical engineering environment. (4) To consider factors in the implementation of a decision making model in the inspection and repair policy with particular reference to the most practical and feasible model investigated.
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Koh, Yeow Leung 1976. "In-situ structural health monitoring of composite repair patches." Monash University, Dept. of Mechanical Engineering, 2002. http://arrow.monash.edu.au/hdl/1959.1/7698.

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BONKAT, BARNABAS NANPAK. "ANALYTICAL PROCEDURE FOR EVALUATING ROADWAY UPGRADING STRATEGY FOR LOW-VOLUME HIGHWAYS." Diss., The University of Arizona, 1985. http://hdl.handle.net/10150/187926.

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The purpose of this research was to develop a simplified analytical procedure for determining the optimal timing for upgrading low-volume roads in developing countries. Most roadway upgradings from gravel to surface treated and to asphaltic concrete are carried out when total transport cost on a road becomes high as a result of high traffic and the consequent rapid deterioration of the roadway. Adequate timing of upgrading strategies ensures effective use of resources and lower total transport cost. This study examined existing systems, models, and approaches for estimating total transport cost components. An analytical procedure was then developed using a decision-tree concept to delineate all possible upgrading strategies within a plan period. The decision-tree concept depicts all the possible upgrading strategies within a plan period with decisions on roadway upgrading made at certain decision intervals. The total transport cost of the upgrading strategies is evaluated to establish the optimal strategies and traffic warrants for improving a roadway surface. A computer program PVMNT was written to facilitate the computation of the total transport cost. A case study was presented to demonstrate the application of the analytical procedure. The case study revealed interesting results on the changes of optimal upgrading strategies with changes in base traffic volume and growth rate. However, general conclusions could not be drawn based on the results of the case study. These results, as well as the analytical procedure, should be of interest to engineers responsible for providing low-volume roads in developing countries.
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Lettovsky, Ladislav. "Airline operations recovery : an optimization approach." Diss., Georgia Institute of Technology, 1997. http://hdl.handle.net/1853/24326.

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Van, den Berg Gideon. "Hidden Markov models for tool wear monitoring in turning operations." Diss., Pretoria : [s.n.], 2004. http://upetd.up.ac.za/thesis/available/etd-05302005-114238/.

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Smith, Ernest Price. "An optimal replacement-design model for a reliable water distribution network system." Diss., Virginia Tech, 1994. http://hdl.handle.net/10919/37455.

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Elwany, Alaa H. "Sensor-based prognostics and structured maintenance policies for components with complex degradation." Diss., Georgia Institute of Technology, 2009. http://hdl.handle.net/1853/37198.

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We propose a mathematical framework that integrates low-level sensory signals from monitoring engineering systems and their components with high-level decision models for maintenance optimization. Our objective is to derive optimal adaptive maintenance strategies that capitalize on condition monitoring information to update maintenance actions based upon the current state of health of the system. We refer to this sensor-based decision methodology as "sense-and-respond logistics". As a first step, we develop and extend degradation models to compute and periodically update the remaining life distribution of fielded components using in situ degradation signals. Next, we integrate these sensory updated remaining life distributions with maintenance decision models to; (1) determine, in real-time, the optimal time to replace a component such that the lost opportunity costs due to early replacements are minimized and system utilization is increased, and (2) sequentially determine the optimal time to order a spare part such that inventory holding costs are minimized while preventing stock outs. Lastly, we integrate the proposed degradation model with Markov process models to derive structured replacement and spare parts ordering policies. In particular, we show that the optimal maintenance policy for our problem setting is a monotonically non-decreasing control limit type policy. We validate our methodology using real-world data from monitoring a piece of rotating machinery using vibration accelerometers. We also demonstrate that the proposed sense-and-respond decision methodology results in better decisions and reduced costs compared to other traditional approaches.
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Moore, Thomas P. "Optimal design, procurement and support of multiple repairable equipment and logistic systems." Diss., Virginia Polytechnic Institute and State University, 1986. http://hdl.handle.net/10919/71158.

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A concept for the mathematical modeling of multiple repairable equipment and logistic systems (MREAL systems) is developed; These systems consist of multiple populations of repairable equipment, and their associated design, procurement, maintenance, and supply support. MREAL systems present management and design problems which parallel the·management and design of multiple, consumable item inventory systems. However, the MREAL system is more complex since it has a repair component. The MREAL system concept is described in a classification hierarchy which attempts to categorize the components of such systems. A specific mathematical model (MREAL1) is developed for a subset of these components. Included in MREAL1 are representations of the equipment reliability and maintainability design problem, the maintenance capacity problem, the retirement age problem, and the population size problem, for each of the multiple populations. MREAL1 models the steady state stochastic behavior of the equipment repair facilities using an approximation which is based upon the finite source, multiple server queuing system. System performance measures included in MREAL1 are: the expected MREAL total system life cycle cost (including a shortage cost penalty); the steady state expected number of shortages; the probability of catastrophic failure in each equipment population; and two budget based measures of effectiveness. Two optimization methods are described for a test problem developed for MREAL1. The first method computes values of the objective function and the constraints for a specified subset of the solution space. The best feasible solution found is recorded. This method can also examine all possible solutions, or can be used in a manual search. The second optimization method performs an exhaustive enumeration. of the combinatorial programming portion of MREAL1, which represents equipment design. For each enumerated design combination, an attempt is made to find the optimal solution to the remaining nonlinear discrete programming problem. A sequential unconstrained minimization technique is used which is based on an augmented Lagrangian penalty function adapted to the integer nature of MREAL1. The unconstrained minimization is performed by a combination of Rosenbrock's search technique, the steepest descent method, and Fibonacci line searches, adapted to the integer nature of the search. Since the model contains many discrete local minima, the sequential unconstrained minimization is repeated from different starting solutions, based upon a heuristic selection procedure. A gradient projection method provides the termination criteria for each unconstrained minimization.
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Collins, Fred C. "Evaluation of a repairable equipment population system and its logistics support subsystem." Thesis, This resource online, 1992. http://scholar.lib.vt.edu/theses/available/etd-10062009-020124/.

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Salazar, Kardozo Alexandros. "A High-Level Framework for the Autonomous Refueling of Satellite Constellations." Thesis, Georgia Institute of Technology, 2007. http://hdl.handle.net/1853/14534.

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Satellite constellations are an increasingly attractive option for many commercial and military applications. They provide a robust and distributed method of accomplishing the goals of expensive monolithic satellites. Among the many challenges that satellite constellations engender (challenges in control, coordination, disposal, and other areas), refueling is of particular interest because of the many methods one can use to refuel a constellation and the lifetime implications on the satellites. The present work presents a methodology for carrying out peer-to-peer refueling maneuvers within a constellation. Peer-to-peer (P2P) refueling can be of great value both in cases where a satellite unexpectedly consumes more fuel than it was alloted, and as part of a mixed refueling strategy that will include an outside tanker bringing fuel to the constellation. Without considering mixed-refueling, we formulate the peer-to-peer refueling problem as an assignment problem that seeks to guarantee that all satellites will have the fuel they need to be functional until the next refueling, while concurrently minimizing the cost in fuel that the refueling maneuvers entail. The assignment problem is then solved via auctions, which, by virtue of their distributed nature, can easily and effectively be implemented on a constellation without jeopardizing any robustness properties. Taking as a given that the P2P assignment problem has been solved, and that it has produced some matching among fuel deficient and fuel sufficient satellites, we then seek to sequence those prescribed maneuvers in the most effective manner. The idea is that while a constellation can be expected to have some redundancy, enough satellites leaving their assigned orbital slots will eventually make it impossible for the constellation to function. To tackle this problem, we define a wide class of operability conditions, and present three algorithms that intelligently schedule the maneuvers. We then briefly show how combining the matching and scheduling problems yields a complete methodology for organizing P2P satellite refueling operations.
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Books on the topic "Repair And Maintenance Of Specific Models"

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Storer, Jay. Chilton's toyota camry 2002-06 repair manual: Covers U.S. and Canadian models of Toyota Camry, Avalon, Solara, and Lexus ES 300/330 models : does not include information specific to the 2005 and 2006 3.5L V6 engine. Newbury Park, CA: Haynes North America, Inc., 2009.

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Layne, Ken. Ford Taurus & Mercury Sable automotive repair manual: Models covered, Ford Taurus and Mercury Sable 1996 through 2005 : does not include information specific to SHO or variable fuel models. Sparkford Nr Yeovil, Somerset, England: Haynes Pub. Group, 2005.

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Maasberg, Wolfgang. Commercial-Industrial Cleaning, by Pressure-Washing, Hydro-Blasting and UHP-Jetting: The Business Operating Model and How-To Manual for 450 Specific Applications. London: Springer London, 2012.

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Harold, Haynes John, ed. Chrysler Sebring, Dodge Stratus & Avenger automotive repair manual: Models covered, Chrysler Sebring convertible, coupe, and sedan (1995 through 2005), Dodge Stratus coupe and sedan (2001 through 2005), Dodge Avenger (1995 through 2000) ; does not include information specific to flexible fuel vehicles. Sparkford, Nr Yeovil, Somerset, England: Haynes Pub. Group, 2006.

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Tadj, Lotfi. Replacement Models with Minimal Repair. London: Springer-Verlag London Limited, 2011.

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Larry, Warren. Mitsubishi FWD models automotive repair manual. Sparkford Nr Yeovil, Somerset, England: Haynes Pub. Group, 1991.

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Larry, Warren, and Larry Warren. Mitsubishi FWD models automotive repair manual. Sparkford Nr Yeovil, Somerset, England: Haynes Pub. Group, 1993.

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Pierce, Judith T. System-specific spare bus ratios. Washington, D.C: National Academy Press, 1995.

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Pierce, Judith T. System-specific spare bus ratios. Washington, DC: National Academy Press, 1990.

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Minkoff, Martin C. System-specific spare bus ratios update. Washington, D.C: Transportation Research Board, 2013.

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Book chapters on the topic "Repair And Maintenance Of Specific Models"

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Wu, Shaomin. "Preventive Maintenance Models: A Review." In Replacement Models with Minimal Repair, 129–40. London: Springer London, 2011. http://dx.doi.org/10.1007/978-0-85729-215-5_4.

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Kijima, Masaaki. "Generalized Renewal Processes and General Repair Models." In Stochastic Models in Reliability and Maintenance, 145–64. Berlin, Heidelberg: Springer Berlin Heidelberg, 2002. http://dx.doi.org/10.1007/978-3-540-24808-8_6.

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Cha, Ji Hwan. "A Survey of Burn-in and Maintenance Models for Repairable Systems." In Replacement Models with Minimal Repair, 179–203. London: Springer London, 2011. http://dx.doi.org/10.1007/978-0-85729-215-5_7.

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Aggoun, Lakhdar, and Lotfi Tadj. "Filtering and M-ary Detection in a Minimal Repair Maintenance Model." In Replacement Models with Minimal Repair, 207–21. London: Springer London, 2011. http://dx.doi.org/10.1007/978-0-85729-215-5_8.

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Kim, Dohoon, Jae-Hak Lim, and Ming J. Zuo. "Optimal Schedules of Two Periodic Imperfect Preventive Maintenance Policies and Their Comparison." In Replacement Models with Minimal Repair, 141–59. London: Springer London, 2011. http://dx.doi.org/10.1007/978-0-85729-215-5_5.

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Syamsundar, A., V. N. A. Naikan, and V. Couallier. "Accelerated Failure Time Models with Corrective and Preventive Maintenance for Repairable Systems Subject to Imperfect Repair." In Reliability, Safety and Hazard Assessment for Risk-Based Technologies, 143–52. Singapore: Springer Singapore, 2019. http://dx.doi.org/10.1007/978-981-13-9008-1_12.

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Greifenberg, Timo, Steffen Hillemacher, and Katrin Hölldobler. "Applied Artifact-Based Analysis for Architecture Consistency Checking." In Ernst Denert Award for Software Engineering 2019, 61–85. Cham: Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-58617-1_5.

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AbstractThe usage of models within model-driven software development aims at facilitating complexity management of the system under development and closing the gap between the problem and the solution domain. Utilizing model-driven software development (MDD) tools for agile development can also increase the complexity within a project. The huge number of different artifacts and relations, their different kinds, and the high degree of automation hinder the understanding, maintenance, and evolution within MDD projects. A systematic approach to understand and manage MDD projects with a focus on its artifacts and corresponding relations is necessary to handle the complexity. The artifact-based analysis presented in this paper is such an approach. This paper gives an overview of different contributions of the artifact-based analysis but focuses on a specific kind of analysis: architecture consistency checking of model-driven development projects. By applying this kind of analyses, differences between the desired architecture and the actual architecture of the project at a specific point in time can be revealed.
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Favi, Claudio, Marco Marconi, Marta Rossi, and Federica Cappelletti. "Product Eco-Design in the Era of Circular Economy: Experiences in the Design of Espresso Coffee Machines." In Lecture Notes in Mechanical Engineering, 194–99. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-70566-4_31.

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AbstractProduct eco-design includes several methodologies aimed at supporting companies in the development of sustainable products. Currently, this theme is assuming an important role in both the academia and industry worlds due to the increasing attention to environmental problems and the need for a transition toward circular economy business/organizational models. In this context, the present paper focuses on the industrial sector of espresso coffee machines manufacturing which has several unexploited potentialities. The analysis of the sector specificity (internal and external contexts), as well as of the product lifecycle allowed to define an eco-design framework to guide companies involved in the design and production of espresso coffee machines. Effective eco-design strategies should include the combined use of specific methods, tools and metrics to manage all the most important lifecycle phases (beginning of life, middle of life, end of life) during the design activities in order to set preventive actions that avoid future potential environmental impacts. Only in this way, the environmental and economic benefits of the circular economy paradigm (e.g. remanufacturing/reuse of selected components) can be practically exploited in real industrial contexts. The presented case studies confirmed that the application of design for disassembly rules positively contributes to increase the product performances during maintenance and end of life, while a re-design oriented to component modularity could be a key strategy to pursue remanufacturing for boilers, a key and expensive component included in espresso coffee machines.
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Olkhovik, Evgeniy, Pavel Garibin, and Vladimir Tsuprik. "Seaport Facilities in Maritime Transport Infrastructure in the Arctic." In Handbook of Research on International Collaboration, Economic Development, and Sustainability in the Arctic, 338–69. IGI Global, 2019. http://dx.doi.org/10.4018/978-1-5225-6954-1.ch016.

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Harbor facilities are important elements of international transport infrastructure. Maintenance of the existing mooring facilities along with the construction of new ports and harborage areas have revealed a number of challenges at all stages of the life cycle. In the Arctic, adverse climate conditions impose specific constraints on the processes of study, engineering, construction, and exploitation of seaport facilities. In this chapter, the authors provide the examples of design solutions as well as specific features of construction and maintenance of seaport facilities in various conditions, suggest technical and hardware solutions for monitoring and safeguard of cargo harbor facilities in the Arctic, measures to reconstruction, repair, utilization, conservation, and elaboration of computational information models. The chapter considers major objectives of environmental safety control during the performance of cargo handling operations, oil spills prevention and response, training and education of hydraulic engineers to perform activities in the Arctic.
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"Maintenance Models with General Degree of Repair." In Reliability and Maintenance, 285–96. Chapman and Hall/CRC, 2012. http://dx.doi.org/10.1201/b12095-18.

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Conference papers on the topic "Repair And Maintenance Of Specific Models"

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Mora, Rafael G., Curtis Parker, Patrick H. Vieth, and Burke Delanty. "Probability of Exceedance (POE) Methodology for Developing Integrity Programs Based on Pipeline Operator-Specific Technical and Economic Factors." In 2002 4th International Pipeline Conference. ASMEDC, 2002. http://dx.doi.org/10.1115/ipc2002-27224.

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With the availability of in-line inspection data, pipeline operators have additional information to develop the technical and economic justification for integrity verification programs (i.e. Fitness-for-Purpose) across an entire pipeline system. The Probability of Exceedance (POE) methodology described herein provides a defensible decision making process for addressing immediate corrosion threats identified through metal loss in-line inspection (ILI) and the use of sub-critical in-line inspection data to develop a long term integrity management program. In addition, this paper describes the process used to develop a Corrosion In-line Inspection POE-based Assessment for one of the systems operated by TransGas Limited (Saskatchewan, Canada). In 2001, TransGas Limited and CC Technologies undertook an integrity verification program of the Loomis to Herbert gas pipeline system to develop an appropriate scope and schedule maintenance activities along this pipeline system. This methodology customizes Probability of Exceedance (POE) results with a deterministic corrosion growth model to determine pipeline specific excavation/repair and re-inspection interval alternatives. Consequently, feature repairs can be scheduled based on severity, operational and financial conditions while maintaining safety as first priority. The merging of deterministic and probabilistic models identified the Loomis to Herbert pipeline system’s worst predicted metal loss depth and the lowest safety factor per each repair/reinspection interval alternative, which when combined with the cost/benefit analysis provided a simplified and safe decision-making process.
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Timashev, S. A., M. G. Malyukova, L. V. Poluian, and A. V. Bushinskaya. "Markov Description of Corrosion Defects Growth and Its Application to Reliability Based Inspection and Maintenance of Pipelines." In 2008 7th International Pipeline Conference. ASMEDC, 2008. http://dx.doi.org/10.1115/ipc2008-64546.

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The paper describes a Markov model of corrosion growth of pipe wall defects and its implementation for assessing the conditional probability of pipeline failure and optimizing pipeline repair and maintenance. This pure growth Markov model is of the continuous time, discrete states type. This model is used in conjunction with the geometrical limit state function (LSF) to assess the conditional probability of failure of pressurized pipelines when the main concern is loss of containment. It is shown how to build an empirical Markov model for the length, depth and width of defects, using field data gathered by In-line inspection (ILI) or direct assessment (DA) or by using a combination of a differential equation (DE) that describes defect parameter growth with the Monte Carlo simulation method. As a result of implementation of this approach the probability for the defect parameters being in a given state (analog of a histogram) and the transition intensities (from state to state) are easily derived for any given moment of time. This approach automatically gives an assessment of the probability of failure of a pipeline segment, as it is derived using the data from a specific pipeline length. This model also allows accounting for the pipeline failure pressure LSF. On the basis of this model an algorithm is constructed for optimizing the time of the next inspection/repair. This methodology is implemented to a specific operating pipeline which was several times inspected by a MFL inspection tool. The expected number and volume of repairs depend on the value of the ultimate permissible pipeline failure probability. Sensitivity of pipeline conditional failure rate and optimal repair time to actual growth rate is investigated. A brief description of the software that implements the described above technology is given.
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Waghmode, Laxman Yadu, and Anil Dattatraya Sahasrabudhe. "On the Expected Number of Failures and Maintenance Cost Prediction of Repairable Systems From Life Cycle Cost Modeling Perspective." In ASME 2010 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. ASMEDC, 2010. http://dx.doi.org/10.1115/detc2010-28044.

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The objective of this paper is to provide some useful insights on how cost driving events are related to the characteristics of failure distributions and the product lifetime (design life) in case of repairable systems. Repairable systems are those that can be restored to their fully operational capabilities by any method, other than the replacement of the entire system. In case of repairable systems, the components can be repaired or adjusted rather than replaced, whenever a breakdown occurs and thus such systems experience multiple failures over their life span. For majority of repairable systems, the life time maintenance and repair costs dominate the life cycle cost. To predict the maintenance and repair cost, failure data, maintenance data and repair time data is needed which is not readily available at the system design stage. When a repairable system is put into service, how many times it will fail over its life span depends on its reliability. Similarly, how fast the system is restored to its working condition when it fails (maintainability), also affect the costs incurred. Thus, the expected number of failures, time lost in restoring the system after each failure and cost per failure are important from life time maintenance cost prediction viewpoint. The expected number of failures depends upon the time to failure distribution of the system components and the after repair state of the system. In this paper, a modeling methodology is suggested for prediction of life time maintenance and repair cost of repairable systems based on expected number of failures. The repairable system lifetime is modeled using a two parameter Weibull distribution. The expected number of failures are estimated for renewal process (as-good-as-new after repair state) and minimal repair process (as-bad-as-old after repair state). The expected maintenance and repair costs are also evaluated for six different failure distributions. The technique has been illustrated through a specific application, namely an industrial pump and the results are presented.
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Elusakin, Tobiloba, Mahmood Shafiee, and Tosin Adedipe. "Towards Implementing Condition-Based Maintenance (CBM) Policy for Offshore Blowout Preventer (BOP) System." In ASME 2019 38th International Conference on Ocean, Offshore and Arctic Engineering. American Society of Mechanical Engineers, 2019. http://dx.doi.org/10.1115/omae2019-95539.

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Abstract With the steadily growing demand for energy in the world, oil and gas companies are finding themselves facing increasing capital and operating costs. To ensure the economic viability of investments and improve the safety of operations, oil and gas companies are promoting their asset integrity management (AIM) systems. In the past, the oil and gas industry adopted reactive maintenance regimes, which involved recertification, testing and repair of faulty equipment while trying to achieve minimum downtime. As technology becomes more affordable, operators have been able to carry out improved fault diagnosis, prognosis and maintenance optimisation. As a result of this, condition-based maintenance (CBM) is being adopted more and more as the preeminent maintenance regime for oil and gas equipment. The blowout preventer (BOP) is one of the most expensive and safety critical drilling equipment in the oil and gas industry. However, there have been very few studies and best practices about how to develop a CBM policy and what specific monitoring techniques and devices will be required to implement it for the BOP system. This paper proposes a V-model based architecture for designing a CBM policy in BOP systems. As a result of the model proposed, gaps in implementation are identified and all the hardware, software and training requirements for implementing the CBM solution in BOP systems will be outlined in detail. Our proposed CBM framework will help BOP operators and maintenance personnel make cost savings through less repairs and replacements and minimal downtime.
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Liu, Xiaoguang, Yongjie Pan, and Xinxin Zhao. "Research on Key Technology of Operation and Maintenance Management of Long Span Railway Steel Bridge Based on BIM." In IABSE Conference, Seoul 2020: Risk Intelligence of Infrastructures. Zurich, Switzerland: International Association for Bridge and Structural Engineering (IABSE), 2020. http://dx.doi.org/10.2749/seoul.2020.222.

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<p>In order to adapt to the development trend of informatization and intelligence of railway bridge operation and maintenance management, the integration of BIM Technology and large-span railway steel bridge operation and maintenance business becomes more and more urgent. Taking one special railway steel bridge as an example, the division levels of bridge structural parts, structural elements and specific components were defined, and the refined BIM model of bridge was established based on the demand of operation and maintenance. The knowledge base systems of component, defect, inspection and maintenance in bridge was formed. The three terminal BIM management system was developed, and the closed-loop management process of bridge inspection, maintenance and repair based on the BIM model was established. At the same time, the monitoring information could be integrated, which can provide the basis for the formation of bridge digital twins. The research results provide a firmly support for data-driven comprehensive evaluation and conditional maintenance of railway steel bridges.</p>
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Reitz, Gerald, Stephan Schlange, and Jens Friedrichs. "Design of Experiments and Numerical Simulation of Deteriorated High Pressure Compressor Airfoils." In ASME Turbo Expo 2016: Turbomachinery Technical Conference and Exposition. American Society of Mechanical Engineers, 2016. http://dx.doi.org/10.1115/gt2016-56024.

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During the operation of a jet engine, deterioration occurs. This constantly affects the engine performance parameters like exhaust gas temperature (EGT) and thrust specific fuel consumption (TSFC). If the EGT reaches a given limit, the engine has to be overhauled during a shop visit at a MRO company (Maintenance, Repair and Overhaul). Using the example of the high pressure compressor (HPC), the airfoils get analyzed for a few geometric properties and classified as serviceable, repairable and non-repairable. The repairable airfoils go through a repair process without in detail considering the actual geometry. To improve the repair process, tailored maintenance actions are desirable. For this purpose, the aerodynamic properties of the airfoil shall be the key factor for defining the repair actions. Therefore, geometric properties with high influence on the aerodynamic performance have to be known to reduce the amount of measuring time. This paper will present a Design of Experiments (DoE) for HPC-airfoil geometry variations. Therefore, 550 different stage setups will be generated, simulated and analyzed. The database will be imported to a Kriging Method to generate a meta-model. Afterwards, the impact of the different geometric properties on the aerodynamic performance, like pressure-, work- and loss coefficients, will be analyzed by using the meta-model. The most important parameters will be determined and their impact on the flow will be explained.
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Branagan, L. A., and S. H. Hesler. "Fundamentals of a Babbitted Bearing Repair Assistant." In ASME 2016 Power Conference collocated with the ASME 2016 10th International Conference on Energy Sustainability and the ASME 2016 14th International Conference on Fuel Cell Science, Engineering and Technology. American Society of Mechanical Engineers, 2016. http://dx.doi.org/10.1115/power2016-59389.

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Fluid film bearings provide critical support for the rotors in gas turbines, steam turbines, generators, exciters and other machines through the generation and support of a hydrodynamic film. Industrial bearings are lined with a babbitt material which serves as a sacrificial element during operation and may need to be refurbished depending on the past operating and maintenance history. After inspection, engineering judgment is typically used during a machine overhaul to determine whether a bearing requires refurbishment. This engineering judgment is developed through an understanding of the principals of bearing design, machine operation, machine monitoring and babbitt wear / damage characteristics. This paper describes the criteria to serve as a basis for a decision support tool relative to the refurbishment of a babbitted, fluid-film bearing. Those criteria start with key descriptors of any damage to the bearing and evaluate the remaining load capacity, repairability, bearing support, rotordynamics influence, journal conditions and pivot conditions. The descriptors focus on visual examinations of the condition of the babbitt and seek to be intuitive, yet remaining comprehensive; to this end a graphical interface is used where feasible. Evaluations include specific load capacity calculations, determination of damage factors for the principal modes of babbitt damage and data from lookup tables whose input is based on experience. These evaluations are combined to provide the basis for the refurbishment decision. Scaling efforts are incorporated into the evaluations to allow their combination into a single bearing condition index. Initial experience suggests that discrete ranges of the bearing condition index are preferable to numerical value. One goal of the tool is to allow use by inexperienced engineers as a support to their technical development. Another goal is to better document the decision process for particular bearings. The preliminary tool was applied to a cylindrical, radial bearing in a horizontal orientation and to a bumper thrust bearing. Initial results have confirmed the general strategy employed and have suggested areas requiring refinement.
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Wessels, William R., Seth Farrington, and Tim Henstock. "Reliability Failure Analysis to Characterize Time-Directed Maintenance Inspection Interval." In ASME 2010 International Mechanical Engineering Congress and Exposition. ASMEDC, 2010. http://dx.doi.org/10.1115/imece2010-38972.

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Reliability failure analysis is performed to implement Reliability-Centered Maintenance, RCM. RCM is implemented by Condition-based Maintenance, CBM, or Time-directed Maintenance, TDM. This paper defines the approach to characterize the time-directed inspection interval for fielded systems in sustainment. The limitation of resources available to the field engineer dictates that neither the incidence nor costs of part failure are sufficient criteria to identify which parts will be selected for transition from unscheduled repair maintenance to RCM. Application of fault tree analysis combined with failure modes, effects and criticality analysis enable a selection process that optimizes the efficiency of operating capital. The FTA and FMECA hypothesize the physical, thermal, and chemical failure mechanisms that act on the part. The hypothesized failure mechanisms are evaluated by math models and simulation to isolate the statistically significant failure mechanisms — the relevant few. Empirical investigation of the statistically significant failure mechanisms begin with nondestructive investigation of control sample parts, to include: visual, microscopic, X-ray, acoustical, and modal inspections. Small scale ‘coupon’ or ‘part’ experiments are designed and performed to model failure behavior for ambient and operational sources of stress loads using accelerated and highly accelerated life test methods. Stress testing is performed on selected test articles at specified intervals to characterize the component strength properties. Data from all tests are fit to a failure model to characterize a time-interval stress-strength frequency distribution from which the reliability functions are inferred using interference theory. The reliability and hazard functions are compared to the specified risk thre4shold to characterize the Time-Directed Maintenance Inspection Interval.
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Wrobel, Michal, Mark Richter, Rene Zimmermann, Holger Kiewel, and Andreas Ullrich. "Rotor Lifecycle Management Program." In ASME Turbo Expo 2014: Turbine Technical Conference and Exposition. American Society of Mechanical Engineers, 2014. http://dx.doi.org/10.1115/gt2014-26761.

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Minimizing the maintenance costs has become an ever growing topic in the power generation industry. Consequently, OEM’s constantly increase their efforts to exploit the full lifetime potential of capital intensive components, as for instance gas turbine rotors. More than ever, it is essential to have a closed loop from the design knowledge to solid facts about the actual condition of a gas turbine rotor in the field, in order to optimize the utilization and therefore to reduce total lifecycle costs. During initial design an iterative component design process is applied, comprising of analytical calculations and component and engine tests, to design a reliable, robust and maintenance friendly component. Individual component risk profiles (i.e. failure probability and consequences) have to be taken into account during the design phase to cover uncertainties regarding the operating regime, operating conditions and environment, resulting in the minimum expected lifetime. The lifetime of gas turbine components is limited and primarily depends on factors like the operating regime, dictating the mechanical and thermal loads, actual material properties, environmental conditions and the level of maintenance. Those parameters have a scatter and also interact with each other. As a consequence the progress of component degradation varies and the individual component lifetime isn’t known in detail at the time of the design. The purpose of a Rotor Lifecycle Management Program is to detect individual component degradation early in the lifecycle, in order to exploit the maximum rotor lifetime while ensuring safe operation. Periodic monitoring and condition assessment of the individual rotor is the first step, performed during standard type C inspections and comprising of visual inspection, dimensional and advanced non-destructive measurements. Typically the monitoring schedule is based on the operating regime and the operating history of the specific rotor. The combination of the monitoring results with validated analytical design models, extensive material data and the overall gas turbine rotor fleet experience of the OEM, allows proper planning of lifetime extension measures, such as repair and reconditioning activities. Specific repair solutions for both on-site and shop applications have been developed. A rotor lifecycle management program is a „living” program. The monitoring scope and schedule as well as the repair solutions portfolio are continuously optimized and adapted as a result of detailed analysis of operating data and inspection results of the whole global fleet.
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Samarakoon, S. M. S. M. K., and R. M. Chandima Ratnayake. "Residual Service Life Prediction of Offshore Concrete Structures With Chloride-Induced Damage: The State of the Art." In ASME 2013 32nd International Conference on Ocean, Offshore and Arctic Engineering. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/omae2013-10460.

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Offshore oil and gas (O&G) production and process facilities (P&PFs) consist of concrete components and structures with steel reinforcement and pre-stressing tendons. They are vulnerable to deterioration due to chloride-induced damage from being exposed to the severe marine environment. The aforementioned deterioration creates significant challenges to the life extension analysis presently required for P&PFs located in the North Sea. Currently, maintenance work has been carried out via in-service inspection and condition monitoring to assure the structural integrity at a pre-specified level of P&PFs. In this context, the knowledge from existing models forms a basis for making quantitative predictions of the remaining service life of structures and components made of concrete. The service life of reinforced concrete structures in relation to reinforcement corrosion is usually modeled considering the initiation period and the corrosion propagation period. The formation of optimal proactive maintenance and repair strategies for corrosion-damaged reinforced concrete (RC) structures is highly dependent on the results of prediction models. The combination of both field (i.e. inspection) and laboratory data with numerical modeling helps the formulation of models for the prediction of the time to pre-defined limit states or to estimate the time for carrying out necessary maintenance and repair. This manuscript provides a review of the available methods for predicting the remaining service life of RC structures in relation to reinforcement corrosion. It also highlights suitable methods for predicting the remaining service life of offshore ageing concrete structures in a severe corrosive environment.
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Reports on the topic "Repair And Maintenance Of Specific Models"

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Fu, Gongkang. Evaluation of Illinois Bridge Deterioration Models. Illinois Center for Transportation, September 2021. http://dx.doi.org/10.36501/0197-9191/21-029.

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The National Bridge Inventory bridge inspection system ranks the condition of bridge components on a scale of zero to nine. The resulting condition ratings represent an important element considered in deciding measures for bridge maintenance, repair, and rehabilitation. Thus, forecasting future condition ratings well is critical to reliable planning for these activities and estimating the costs. The Illinois Department of Transportation currently has deterministic models for this purpose. This study’s objective is to review the current models using condition rating histories gathered from 1980 to 2020 in Illinois for the following bridge components: deck, superstructure, substructure, culvert, and deck beam. The results show the current Illinois Department of Transportation models are inadequate in forecasting condition ratings, producing overestimates of the transition times between two condition rating levels for these components / systems, except for the deck beam, which is underestimated. It is recommended that the mean transition times found in this study from condition rating histories are used to replace the current models as a short-term solution. Further research is recommended to develop probabilistic models as a long-term solution to address observed significant variation or uncertainty in condition rating and transition times between condition rating levels.
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