This page has only limited features, please log in for full access.
Underground pipelines are an essential part of the transportation infrastructure. The structural deterioration of pipelines crossing railways and their subsequent failures can entail critical consequences for society and industry, resulting in direct and indirect costs for all the stakeholders involved. Therefore, continuous and accurate condition assessment is critical for the effective management and maintenance of pipeline networks within the transportation infrastructure. The aim of this study has been to identify failure modes and consequences related to pipelines crossing railway corridors. Expert opinions have been collected through interviews and two sets of questionnaires have been distributed to the 291 municipalities in Sweden, with 137 responses in total. The failure analysis has revealed that pipe deformation has the highest impact, followed by pipe rupture at locations where pipelines cross railway infrastructure. For underground pipelines under railway infrastructure, ageing and the external load were awarded a higher ranking than other potential causes of pipeline failure.
A. H. S. Garmabaki; Stefan Marklund; Adithya Thaduri; Annelie Hedström; Uday Kumar. Underground pipelines and railway infrastructure – failure consequences and restrictions. Structure and Infrastructure Engineering 2019, 16, 412 -430.
AMA StyleA. H. S. Garmabaki, Stefan Marklund, Adithya Thaduri, Annelie Hedström, Uday Kumar. Underground pipelines and railway infrastructure – failure consequences and restrictions. Structure and Infrastructure Engineering. 2019; 16 (3):412-430.
Chicago/Turabian StyleA. H. S. Garmabaki; Stefan Marklund; Adithya Thaduri; Annelie Hedström; Uday Kumar. 2019. "Underground pipelines and railway infrastructure – failure consequences and restrictions." Structure and Infrastructure Engineering 16, no. 3: 412-430.
An automatic, fast, and accurate switching method between Global Positioning System and indoor positioning systems is crucial to achieve current user positioning, which is essential information for a variety of services installed on smart devices, e.g., location-based services (LBS), healthcare monitoring components, and seamless indoor/outdoor navigation and localization (SNAL). In this study, we proposed an approach to accurately detect the indoor/outdoor environment according to six different daily activities of users including walk, skip, jog, stay, climbing stairs up and down. We select a number of features for each activity and then apply ensemble learning methods such as Random Forest, and AdaBoost to classify the environment types. Extensive model evaluations and feature analysis indicate that the system can achieve a high detection rate with good adaptation for environment recognition. Empirical evaluation of the proposed method has been verified on the HASC-2016 public dataset, and results show 99% accuracy to detect environment types. The proposed method relies only on the daily life activities data and does not need any external facilities such as the signal cell tower or Wi-Fi access points. This implies the applicability of the proposed method for the upper layer applications.
Aghil Esmaeili Kelishomi; A.H.S. Garmabaki; Mahdi Bahaghighat; Jianmin Dong. Mobile User Indoor-Outdoor Detection Through Physical Daily Activities. Sensors 2019, 19, 511 .
AMA StyleAghil Esmaeili Kelishomi, A.H.S. Garmabaki, Mahdi Bahaghighat, Jianmin Dong. Mobile User Indoor-Outdoor Detection Through Physical Daily Activities. Sensors. 2019; 19 (3):511.
Chicago/Turabian StyleAghil Esmaeili Kelishomi; A.H.S. Garmabaki; Mahdi Bahaghighat; Jianmin Dong. 2019. "Mobile User Indoor-Outdoor Detection Through Physical Daily Activities." Sensors 19, no. 3: 511.
A.H.S Garmabaki; Uday Kumar; Adithya Thaduri; Annelie Hedström; Jan Laue; Stefan Marklund; Johan Odelius; Matti Rantatalo; Mattias Asplund; Tarun Bansal; Stefan Indahl. A Survey on Underground Pipelines and Railway Infrastructure at Cross-Sections. Proceedings of the 29th European Safety and Reliability Conference (ESREL) 2019, 1 .
AMA StyleA.H.S Garmabaki, Uday Kumar, Adithya Thaduri, Annelie Hedström, Jan Laue, Stefan Marklund, Johan Odelius, Matti Rantatalo, Mattias Asplund, Tarun Bansal, Stefan Indahl. A Survey on Underground Pipelines and Railway Infrastructure at Cross-Sections. Proceedings of the 29th European Safety and Reliability Conference (ESREL). 2019; ():1.
Chicago/Turabian StyleA.H.S Garmabaki; Uday Kumar; Adithya Thaduri; Annelie Hedström; Jan Laue; Stefan Marklund; Johan Odelius; Matti Rantatalo; Mattias Asplund; Tarun Bansal; Stefan Indahl. 2019. "A Survey on Underground Pipelines and Railway Infrastructure at Cross-Sections." Proceedings of the 29th European Safety and Reliability Conference (ESREL) , no. : 1.
Automotive manufacturing industries are required to improve their productivity with higher production rates at the lowest cost, less number of unexpected shutdowns, and reliable operation. In order to achieve the above objectives, the application of reliability, availability, and maintainability methodologies can constitute for resilient operation, identifying the bottlenecks of manufacturing process and optimization of maintenance actions. In this article, we propose a framework for reliability, availability, and maintainability evaluation and maintenance optimization to improve the performance of conveying process of vehicle body in an automotive assembly line. The results of reliability, availability, and maintainability analysis showed that the reliability and maintainability of forklift and loading equipment are the main bottlenecks. To find the optimal maintenance intervals of each unit, a multi-attribute utility theory is applied for multi-criteria decision model considering reliability, availability, and costs. Due to the series configuration of conveying process in automotive assembly line, the optimized time intervals are obtained using opportunistic maintenance strategy. The results could be useful to improve operational performance and sustainability of the production process.
Hamzeh Soltanali; A.H.S Garmabaki; Adithya Thaduri; Aditya Parida; Uday Kumar; Abbas Rohani. Sustainable production process: An application of reliability, availability, and maintainability methodologies in automotive manufacturing. Proceedings of the Institution of Mechanical Engineers, Part O: Journal of Risk and Reliability 2018, 233, 682 -697.
AMA StyleHamzeh Soltanali, A.H.S Garmabaki, Adithya Thaduri, Aditya Parida, Uday Kumar, Abbas Rohani. Sustainable production process: An application of reliability, availability, and maintainability methodologies in automotive manufacturing. Proceedings of the Institution of Mechanical Engineers, Part O: Journal of Risk and Reliability. 2018; 233 (4):682-697.
Chicago/Turabian StyleHamzeh Soltanali; A.H.S Garmabaki; Adithya Thaduri; Aditya Parida; Uday Kumar; Abbas Rohani. 2018. "Sustainable production process: An application of reliability, availability, and maintainability methodologies in automotive manufacturing." Proceedings of the Institution of Mechanical Engineers, Part O: Journal of Risk and Reliability 233, no. 4: 682-697.
In practice, the analyst is often dealing with multiple repairable units, installed in different positions or functioning under different operating conditions, and maintained by different disciplines. This paper presents a decision framework to identify an appropriate reliability model for massive multiple repairable units. It splits non-homogeneous failure data into homogeneous groups and classifies them based on their failure trends using statistical tests. The framework discusses different scenarios for analysing multiple repairable units, according to trend, intensity, and dependency of the units׳ failure data. The proposed framework has been verified in a fleet of aircraft and in two simulated data sets. The results show a reliability model of multiple repairable units may contain a mixture of different stochastic models. Considering single reliability models for such populations may cause erroneous calculation of the time to failure of a particular unit, which can, in turn, lead to faulty conclusions and decisions. When dealing with massive and non-homogeneous multiple repairable units, the application of the proposed framework can facilitate the selection of an appropriate reliability model.
A.H.S. Garmabaki; Alireza Ahmadi; Jan Block; Hoang Pham; Uday Kumar. A reliability decision framework for multiple repairable units. Reliability Engineering & System Safety 2016, 150, 78 -88.
AMA StyleA.H.S. Garmabaki, Alireza Ahmadi, Jan Block, Hoang Pham, Uday Kumar. A reliability decision framework for multiple repairable units. Reliability Engineering & System Safety. 2016; 150 ():78-88.
Chicago/Turabian StyleA.H.S. Garmabaki; Alireza Ahmadi; Jan Block; Hoang Pham; Uday Kumar. 2016. "A reliability decision framework for multiple repairable units." Reliability Engineering & System Safety 150, no. : 78-88.
Nowadays, software companies have to continuously do up-gradation or add-ons in their software to survive in the market. This paper presents an effective reliability model for multi release open source software (OSS), which derived based on software lifecycle development process (SDLC) proposed by Jørgensen [1]. Most of OSS reliability models proposed in the literature are based on closed-form methodology and do not consider the properties of OSS in the model structure. The proposed model, incorporate bugs removed from two different phases, namely a pre-commit test and parallel debugging test. Furthermore, the proposed model is based on the assumptions that the overall fault removal of the new release depends on the reported faults from the previous release of the software and on the faults generated due to adding some new functionalities to the existing software system. The parameters of model have been estimated on real software failure dataset with three releases and goodness of fit of values have been calculated. Results show that the proposed model fits the data reasonably well and present better accuracy in comparison with other methods.
Mahdieh Ahmadi; Iraj Mahdavi; A. H. S. Garmabaki. Multi Up-Gradation Reliability Model for Open Source Software. Proceedings of the 2nd Annual International Conference on Material, Machines and Methods for Sustainable Development (MMMS2020) 2015, 691 -702.
AMA StyleMahdieh Ahmadi, Iraj Mahdavi, A. H. S. Garmabaki. Multi Up-Gradation Reliability Model for Open Source Software. Proceedings of the 2nd Annual International Conference on Material, Machines and Methods for Sustainable Development (MMMS2020). 2015; ():691-702.
Chicago/Turabian StyleMahdieh Ahmadi; Iraj Mahdavi; A. H. S. Garmabaki. 2015. "Multi Up-Gradation Reliability Model for Open Source Software." Proceedings of the 2nd Annual International Conference on Material, Machines and Methods for Sustainable Development (MMMS2020) , no. : 691-702.
Several factors such as reliability, availability, and cost may consider in the maintenance modeling. In order to develop an optimal inspection program, it is necessary to consider the simultaneous effect of above factor in the model structure. In addition, for finding the optimal maintenance interval it is necessary to make trade-offs between several factors, which may conflicting each other as well. The study comprises of mathematical formulating an optimal interval problem based on Multi-Attribute Utility Theory (MAUT). The aim of the proposed research is to develop a methodology with supporting tools for determination of optimal inspection in a maintenance planning to assure and preserve a desired level of performance measure such as reliability, availability, risk, etc. For verification and validation purposes, the proposed methodology (analysis approach) and tools (models) will be applied in a real case which given by the literature.
A. H. S. Garmabaki; Alireza Ahmadi; Mahdieh Ahmadi. Maintenance Optimization Using Multi-attribute Utility Theory. Recent Advances in Computational Mechanics and Simulations 2015, 13 -25.
AMA StyleA. H. S. Garmabaki, Alireza Ahmadi, Mahdieh Ahmadi. Maintenance Optimization Using Multi-attribute Utility Theory. Recent Advances in Computational Mechanics and Simulations. 2015; ():13-25.
Chicago/Turabian StyleA. H. S. Garmabaki; Alireza Ahmadi; Mahdieh Ahmadi. 2015. "Maintenance Optimization Using Multi-attribute Utility Theory." Recent Advances in Computational Mechanics and Simulations , no. : 13-25.