Annual Symposium Reliability and Maintainability, 2004 - RAMS最新文献

{"title":"A methodology to quantify some IVHM requirements during RLV conceptual design","authors":"K. Datta, D. Squires","doi":"10.1109/RAMS.2004.1285495","DOIUrl":"https://doi.org/10.1109/RAMS.2004.1285495","url":null,"abstract":"Based on high level safety and cost requirements, system architects and subsystem engineers are called upon to provide requirements at a lower level during the conceptual design phase of a reusable launch vehicle (RLV). This paper describes an event tree based methodology for quantitatively assessing the limits of some of the lower-level integrated vehicle health management (IVHM) requirements during RLV conceptual design. The metrics assessed in the paper are fault detection coverage, false alarm probability, fault isolation capability, probability of IVHM failing to detect a fault, and safety allocation. The fault detection and isolation metrics were assessed based on their applicability with respect to cost and safety in the mission and turnaround phase of the RLV operations. The paper shows that the mission-phase requirement for IVHM fault detection coverage for a subsystem is large (more stringent) when IVHM needs to make the subsystem safer, the failure remediation probability is small, and the subsystem is already reliable. The requirement on IVHM false alarm rate in the mission phase is small (more stringent) when the subsystem is reliable, IVHM needs to make the subsystem safer, and IVHM should cause fewer false aborts. The paper concludes by stressing the use of appropriate system analysis and optimization in allocating IVHM requirements to a subsystem of the RLV. Although the paper is written from an IVHM and RLV perspective, it is targeted towards system engineers/architects who are interested in estimating the effects of fault detection and isolation requirements during conceptual design.","PeriodicalId":270494,"journal":{"name":"Annual Symposium Reliability and Maintainability, 2004 - RAMS","volume":"27 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-08-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117214421","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Extended fault modeling used in the space shuttle PRA","authors":"W. Vesely","doi":"10.1109/RAMS.2004.1285479","DOIUrl":"https://doi.org/10.1109/RAMS.2004.1285479","url":null,"abstract":"A probabilistic risk assessment (PRA) has been completed for the space shuttle with NASA sponsorship and involvement. This current space shuttle PRA is an advancement over past PRAs conducted for the space shuttle in the technical approaches utilized and in the direct involvement of the NASA centers and prime contractors. One of the technical advancements is the extended fault modeling techniques used. A significant portion of the data collected by NASA for the space shuttle consists of faults, which are not yet failures but have the potential of becoming failures if not corrected. This fault data consists of leaks, cracks, material anomalies, and debonding faults. Detailed, quantitative fault models were developed for the space shuttle PRA which involved assessing the severity of the fault, detection effectiveness, recurrence control effectiveness, and mission-initiation potential. Each of these attributes was transformed into a quantitative weight to provide a systematic estimate of the probability of the fault becoming a failure in a mission. Using the methodology developed, mission failure probabilities were estimated from collected fault data. The methodology is an application of counter-factual theory and defect modeling which produces consistent estimates of failure rates from fault rates. Software was developed to analyze all the relevant fault data collected for given types of faults in given systems. The software allowed the PRA to be linked to NASA's fault databases. This also allows the PRA to be updated as new fault data is collected. This fault modeling and its implementation with FRAS was an important part of the space shuttle PRA.","PeriodicalId":270494,"journal":{"name":"Annual Symposium Reliability and Maintainability, 2004 - RAMS","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-08-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127711336","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Intelligent FMEA based on model FIORN","authors":"Zhao Tingdi, Su Tiejun, He Xiao, Sun Linling","doi":"10.1109/RAMS.2004.1285480","DOIUrl":"https://doi.org/10.1109/RAMS.2004.1285480","url":null,"abstract":"FMEA automation and intelligence are studied, which is an effective way to improving FMEA in product development. Firstly, we formed an intelligent FMEA framework that is an intelligent failure effect inference mechanism based on the target system model as well as using expert experience and considering failure modes input and output relationship between products in the system. This framework is comprised of three parts, failure mode analyzer, failure effect analyzer and FMEA report creator. Failure effect analysis based on system models. We form two system modeling methods, system hierarchical model based on expert knowledge and fault input/output relationship net (FIORN) model which describes the relationship among products belonging to the same level in the system. The latter based on failures' relationship and it could analyse correlated failures and common cause failures. Inference mechanism is presented based on these two models. Lastly, a prototype software - iFMEA (intelligent FMEA) is developed. Intelligent FMEA technique is used in analysis of an aircraft's main gear system through which detail steps of intelligent FMEA method are described. System modeling method and inference mechanism are validated by this example.","PeriodicalId":270494,"journal":{"name":"Annual Symposium Reliability and Maintainability, 2004 - RAMS","volume":"32 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-08-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121352677","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"An analysis of the drivers in the philosophy of reliability practice over the last 50 years","authors":"P. Taksakulvith, J.A. Jones, L. Warrington","doi":"10.1109/RAMS.2004.1285430","DOIUrl":"https://doi.org/10.1109/RAMS.2004.1285430","url":null,"abstract":"Over the last 50 years reliability has come a long way, this is often due to the work of many minor figures and numerous small improvements in practice but as in any human endeavour there have been, and are, major figures with much influence and large forces for change and these will cause significant, sudden changes. Work has been carried out at the University of Warwick to understand the development of the philosophy that underpins much of what we as reliability professionals do. This work has enabled the construction of a timeline of change in a number of the fields and techniques of reliability. The timelines highlight the influences and identify the driving forces behind much of what we would now term the state of the art. This paper describes one of these timelines, the development of the linked fields of physics of failure and of reliability prediction. It is apparent to the authors that many industrial areas follow slightly different philosophies. These different philosophies may be identifiable at different points on the time line and may have led to parallel development. Work has therefore also taken place to position certain industries in their respective places and to examine the possible routes available to them for further development of reliability practice.","PeriodicalId":270494,"journal":{"name":"Annual Symposium Reliability and Maintainability, 2004 - RAMS","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-08-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121440899","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A prediction based design-for-reliability tool","authors":"B. Edson, X. Tian","doi":"10.1109/RAMS.2004.1285484","DOIUrl":"https://doi.org/10.1109/RAMS.2004.1285484","url":null,"abstract":"In today's short product lifecycles, it is especially important to apply design for reliability (DFR) practices as early as possible. Since decisions about which reliability features should be included in a design occur in the context of a system design trade-off process, there then needs to be some way to help design engineers decide which DFR actions have sufficient benefit to outweigh other concerns. An approach to giving design engineers feedback to their decisions from a reliability perspective by using the reliability prediction process is presented. Specific DFR practices are linked to parameters in a reliability prediction model, and a sensitivity analysis allows the design engineer understand the relationship between their choices and the predicted failure rate of the system when it is fielded. An initial implementation of this approach using a standard reliability prediction model, the Telcordia (Bellcore) parts stress prediction model, and some standard rules of thumb from the reliability analysis center's reliability toolkit is described. Finally plans for future evolution and improvement in this approach is discussed.","PeriodicalId":270494,"journal":{"name":"Annual Symposium Reliability and Maintainability, 2004 - RAMS","volume":"56 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-08-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116101532","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Forecasting models for maintenance work load with seasonal components","authors":"I. A. Salman","doi":"10.1109/RAMS.2004.1285499","DOIUrl":"https://doi.org/10.1109/RAMS.2004.1285499","url":null,"abstract":"This paper presents the results of applying time series forecasting techniques to the forecasting of maintenance work load. In particular, this paper discusses several models developed to forecast the electronics maintenance work load for a weather forecasting system located in Alaska. The maintenance work load for this system typically increases during the winter season. This is mostly due to the system's remote geographic locations and the additional travel time required to reach these locations during the harsh Alaskan winter. Several models were developed and evaluated on the basis of their data fit and forecasting accuracy of seasonal and non-seasonal electronics maintenance work load. In the first part of the analysis, a regression model that uses a serial autocorrelated error correction procedure was developed to model the non-seasonal components of the work load. Seasonal work load components were modeled using seasonal and cyclical indicator variables. The cyclical indicator variables were effective in modeling this system's seasonal work load behavior. A model that uses a combination of seasonal and cyclical indicator variables was also effective in this respect. In the second part of the analysis, seasonal autoregressive integrated moving average (ARIMA) techniques were used to model and forecast maintenance work load. A brief description of these forecasting methods and the procedures used to identify an optimal work load forecasting model are provided. Two seasonal ARIMA models were developed: The first model used only maintenance predictor variables; the second model used a combination of maintenance predictor variables and cyclical indicator variables. All of the models were evaluated on the basis of their goodness-of-fit and forecasting accuracy. A seasonal ARIMA model that uses a combination of maintenance predictor variables and cyclical indicator variables had the best goodness-of-fit and provided the most accurate maintenance work load forecast. Cyclical indicator variables were found to be extremely effective in modeling the seasonal behavior of the maintenance work load in both the causal and stochastic models.","PeriodicalId":270494,"journal":{"name":"Annual Symposium Reliability and Maintainability, 2004 - RAMS","volume":"92 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-08-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114154343","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Improving engine control reliability through software optimization","authors":"M. Phadke, L. Smith","doi":"10.1109/RAMS.2004.1285518","DOIUrl":"https://doi.org/10.1109/RAMS.2004.1285518","url":null,"abstract":"This paper discusses optimization of software control strategy for eliminating \"hitching\" and \"ringing\" in a diesel engine powertrain. Slow- and high-amplitude oscillation of the entire vehicle powertrain under steady pedal position at idle is called \"ringing\", and similar behavior under cruisecontrol conditions is called \"hitching\". The intermittent nature of these conditions posed a particular challenge in arriving at proper design alternatives. Zero-point-proportional dynamic S/N ratio was used to quantify vibration and tracking accuracy under six driving conditions, which represented noise factors. An L1 8 orthogonal array explored combinations of six software strategy control factors associated with controlling fuel delivery to the engine. The result was between 4 and 10 dB improvement in vibration reduction, resulting in virtual elimination of the hitching condition. As a result of this effort, a 12 Repair/1000 vehicle reliability (eight million dollar warranty) problem was eliminated. The robust design methodology developed in this application may be used for a variety of applications to optimize similar feedback control strategies.","PeriodicalId":270494,"journal":{"name":"Annual Symposium Reliability and Maintainability, 2004 - RAMS","volume":"08 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-08-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127373640","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A comprehensive hardware reliability program for developing a carrier grade telecom product","authors":"M. Radojicic, D. Ragwar, A. Vo","doi":"10.1109/RAMS.2004.1285488","DOIUrl":"https://doi.org/10.1109/RAMS.2004.1285488","url":null,"abstract":"A design methodology was developed to balance the need of a telecom network equipment provider to quickly release products that meet carrier customers' requirements for demonstrated highly reliable network equipment and the customers need to have stable, reliable and inexpensive equipment. The reliability program value is confirmed through the creation of an accurate system availability model and, with its application, the resultant ten-fold decrease in system downtime. A process for the validating all assumptions and conclusions is also discussed.","PeriodicalId":270494,"journal":{"name":"Annual Symposium Reliability and Maintainability, 2004 - RAMS","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-08-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126899568","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A comparison of reliability methods and the REMM process","authors":"J. Marshall, D. Lumbard, J. Davies, G. Tanner","doi":"10.1109/RAMS.2004.1285477","DOIUrl":"https://doi.org/10.1109/RAMS.2004.1285477","url":null,"abstract":"This paper describes conventional methods of reliability prediction and their uses. It also describes the REMM process and the REMM statistical model. Examples of using the REMM process are shown from 4 aerospace companies and a comparison made between the REMM process and conventional reliability approaches. The paper concludes by listing the advantages and disadvantages of using the REMM process as compared to conventional reliability methods.","PeriodicalId":270494,"journal":{"name":"Annual Symposium Reliability and Maintainability, 2004 - RAMS","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-08-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126829269","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Reliability data collection and analysis system","authors":"G.J. Groen, Siyuan Jiang, A. Mosleh, E. Droguett","doi":"10.1109/RAMS.2004.1285421","DOIUrl":"https://doi.org/10.1109/RAMS.2004.1285421","url":null,"abstract":"This paper presents ReDCAS, the reliability data collection and analysis system. ReDCAS is a software tool for reliability data collection and analysis developed for Ford Motor Company. The software employs Bayesian data analysis techniques to estimate reliability measures based on warranty data, test data, and engineering judgments regarding the impact of design changes on the reliability. The software was developed over the period 1995-1999, and has been used to perform reliability assessments for products under development. ReDCAS provides a working environment for engineers provide engineers to incorporate reliability considerations into the design or redesign of products, even though data on the actual product under design is lacking or absent. This is achieved by basing reliability assessments on data available for different, yet similar products. By considering that these products will typically have similar reliability characteristics, this data can be considered (partially) relevant to the estimation of the new product's reliability characteristics. Incorporation of the data into the assessment requires that corrections are made based on the anticipated reliability impact of design modifications. Similarly, prototype life test data is incorporated into reliability assessments, considering the effectiveness of the design corrective action to those failures observed during the tests. Analyses are performed using Bayesian data analysis procedures. The reliability behavior is modeled via the Weibull and increasing decreasing bathtub (IDB) models. The latter model is a three parameter model capable of representing bathtub-shaped failure rate functions. The procedures provide reliability estimates in the form of reliability and failure rate estimates, plus associated uncertainties.","PeriodicalId":270494,"journal":{"name":"Annual Symposium Reliability and Maintainability, 2004 - RAMS","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-08-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125066489","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}