18 research outputs found
A Method for Identifying the Key Performance Shaping Factors to Prevent Human Errors during Oil Tanker Offloading Work
Acknowledgments: The authors would like to appreciate the experts and the engineers working in the Beihai Oil Terminal for their constructive supports during the development of this work. The authors would also like to thank the editors and the anonymous reviewers for their valuable comments.Peer reviewedPublisher PD
Geometric and kinematic analysis of faults bordering the Andaman sea continental shelves: a 3D seismic case study
To clarify the tectonic evolution of M15 block in the Andaman Sea, we perform a delicate study of fault geometry and dynamics using a 3D seismic data. The data reveal eight sequence interfaces from the Early Oligocene to the Quaternary, large scale and multi angle extensional strike-slip faults, and a series of normal faults. The two large scale faults F1 and F2 start in the Eocene and end in the Quaternary, controlling the regional structure. The NNE-SSW strike-slip F1 fault belongs to the South Sagaing fault and the NNE-SSW strike-slip F2 is the eastern Andaman fault, the strike-slip movement of which are controlled by the impact of the collision between the Indian plate and the Eurasian plate. Through the analysis of the fault development history by the method of the ancient drop and the growth index, we find that most of the large or secondary scale faults reach the maximum drop and growth index in the Miocene, indicating that the Miocene is a significant period of plate collision enhancing and faults generating. The regional stress field is dominated by E-W tension. The continental crust has expanded rapidly from the Oligocene to the Miocene which results in the rapid subsidence of the crust. This regional stress intensity becomes weak after the Miocene. The activities of the faults caused a large difference in terrain height between the west and the east in the study area, forming a pattern of the western depression and the eastern terrace. Many NNE-SSW, NE-SW or NEE-SWW trend strike-slip faults and minor faults develop in the Miocene. It echoes the event that the convergence and subduction of the Indian plate from SW to NE direction led to the right rotation and N-NNE strike-slip of the West Myanmar block in the Miocene, thus forming a regional large strike-slip fault. All of the faults affect the structure of the region
Modélisation des patterns d'analyse des performances des systèmes de production et de sûreté de fonctionnement dans l'industrie des procédés
Production and safety systems are crucial in the process industry. Their performances affect significantly the industry interests. These systems have common behaviors. Such behaviors can be captured in models via modeling patterns. By reusing modeling patterns, the modeling process can be simplified and made more efficient.In this thesis, we propose a versatile set of modeling patterns. They are classified according to their purpose, which reflects what a modeling pattern works for. Modeling patterns are exhibited as a catalog. Based on reviewing numerous production and safety systems, twenty-four (24) modeling patterns are introduced. Each pattern is illustrated with a set of structured items. We propose a pattern-based methodology for performance analysis of production and safety systems.To test the applicability of proposed modeling patterns, we conducted experimental studies on a set of production and safety systems. All systems are extracted from the literature. These systems are declared to cover most of modeling difficulties. Comparisons are performed between the results obtained using modeling patterns and those reported in the literature.Les systèmes de production et de sûreté de fonctionnement sont d'une importance majeure dans l'industrie des procédés. Leurs performances impactent directement les intérêts de l'industrie. Ces systèmes ont des comportements similaires. Ces comportements peuvent être conceptualisés dans des modèles via des patterns de modélisation. La réutilisation de ces patterns permet de rendre le processus de modélisation à la fois simplifiée et plus efficace.Dans cette thèse, nous proposons un ensemble varié de patterns de modélisation. Ils sont classés en fonction de leur usage, ce qui reflète le fonctionnement d'un pattern de modélisation. Les patterns sont présentés sous forme d’un catalogue. Sur la base de l'étude de nombreux systèmes de production et de sécurité, vingt-quatre (24) patterns de modélisation sont introduits. Chaque pattern est représenté par un ensemble d'éléments structurés. Nous proposons une méthodologie basée sur les patterns pour l'analyse des performances des systèmes de production et de sûreté de fonctionnement.Pour tester la pertinence des patterns de modélisation suggérés, nous avons mené des études expérimentales sur un ensemble de systèmes de production et de sûreté. Tous les systèmes de validation sont extraits de la littérature. Ces systèmes traitent la majorité des difficultés de modélisation détectées auparavant. Une comparaison est effectuée entre les résultats obtenus en utilisant la modélisation basée sur les patterns et ceux rapportés dans la littérature
A method for economic evaluation of predictive maintenance technologies by integrating system dynamics and evolutionary game modelling
International audiencePredictive maintenance technologies can be employed for failure prediction and system health management. Nevertheless, the additional cost involved in establishing the predictive maintenance system can be an obstacle to its widespread application. The decision on the predictive maintenance technology adoption can be made through the computation of the return on investment. To investigate the mechanisms of dynamic game between stakeholders involved in predictive maintenance, we establish the SD-EGT model from the perspective of systems engineering. This paper aims to propose an integrated method for the economic evaluation of predictive maintenance technologies by considering the incremental costs and benefits associated with its deployment. As an exemplary case, we take the Lithium-ion batteries whose failures have led to unexpected safety accidents. Firstly, we construct a quantitative relationship model between the failure modes and the predictive benefits of Lithium-ion battery systems to quantify the incremental benefits. Then, we establish a cost-benefit analysis (CBA) model by using system dynamics (SD) to make decisions about cost-effectiveness. Secondly, to optimize the cost investment strategy for the predictive maintenance technology, we develop an enterprise-government evolutionary game model, considering the information asymmetry between players. Eventually, we conduct a sensitivity analysis of the static subsidy strategy. The proposed methodology is serviceable to optimize the decision-making of predictive maintenance technology investment, which is a difficult yet very important task in industrial practice
A hybrid method for prognostics of lithium-ion batteries capacity considering regeneration phenomena
International audiencePrognostics and health management (PHM) is crucial to the reliability and safety of lithium-ion batteries. In this respect, the capacity regeneration phenomenon that occurs during the process of battery degradation brings a challenge to the accuracy of capacity prediction. In this paper, a hybrid method is proposed for the accurate prediction of lithium-ion batteries capacity considering regeneration. Firstly, the complete ensemble empirical mode decomposition with adaptive noise (CEEMDAN) is applied to decompose the raw capacity signal into the global degradation trend components and the local fluctuation components. Then, each component is separately fed to the adaptive neuro-fuzzy inference system (ANFIS) for prediction. Finally, the individual outputs of the ANFIS models are recomposed to obtain the ultimate prediction results. The proposed method is validated by application to NASA lithium-ion battery experimental data. The results obtained show that the proposed method can obtain satisfactory prediction accuracy, wherein the negative impact of capacity regeneration on the prediction accuracy is reduced
Disponibilité de production du système en mer en utilisant AltaRica 3.0
Dans cet article, nous présentons une étude destinée à évaluer la disponibilité d'une unité flottante de production, de stockage et de déchargement (FPSO: Floating Production Storage and Offloading unit) réalisée avec le langage de modélisation AltaRica 3.0. L'objectif principal de notre travail était d'identifier les paramètres sensibles et les composants critiques à l'égard de la disponibilité de la production. Prendre en compte les paramètres sensibles et s’assurer du bon fonctionnement des composants critiques peut permettre de garantir une disponibilité et une production élevées du système de production offshore.In this article, we show the application of the AltaRica 3.0 modeling language for assessing the production availability of a Floating Production Storage and Offloading system (FPSO). The main objective of our study is to identify the sensitive parameters and crucial components with respect to the production availability. Taking care of the sensitive parameters and ensuring the well working status of crucial components can guarantee a relative high production availability of the offshore production system
An integrated methodology for dynamic risk prediction of thermal runaway in lithium-ion batteries
The risk of thermal runaway in lithium-ion battery (LIB) attracts significant attention from domains of society, industry, and academia. However, the thermal runaway prediction in the framework of system safety requires further efforts. In this paper, we propose a methodology for dynamic risk prediction by integrating fault tree (FT), dynamic Bayesian network (DBN) and support vector regression (SVR). FT graphically describes the logic of mechanism of thermal runaway. DBN allows considering multiple states and uncertain inference for providing quantitative results of the risk evolution. SVR is subsequently utilized for predicting the risk from the DBN estimation. The proposed methodology can be applied for risk early warning of LIB thermal runaway
Production performance of an offshore system by applying AltaRica 3.0
International audienceDans cet article, nous présentons une étude destinée à évaluer la disponibilité d'une unité flottante de production, de stockage et de déchargement (FPSO: Floating Production Storage and Offloading unit) réalisée avec le langage de modélisation AltaRica 3.0. L'objectif principal de notre travail était d'identifier les paramètres sensibles et les composants critiques à l'égard de la disponibilité de la production. Prendre en compte les paramètres sensibles et s’assurer du bon fonctionnement des composants critiques peut permettre de garantir une disponibilité et une production élevées du système de production offshoreIn this article, we show the application of the AltaRica 3.0 modeling language for assessing the production availability of a Floating Production Storage and Offloading system (FPSO). The main objective of our study is to identify the sensitive parameters and crucial components with respect to the production availability. Taking care of the sensitive parameters and ensuring the well working status of crucial components can guarantee a relative high production availability of the offshore production system
A system dynamics model of offshore wind farm degradation: Enabling operation and maintenance planning under foreseen asset management impacts
This paper presents a system dynamics model to for the degradation of offshore wind farms (OWFs) optimise O&M planning and asset management, taking into account the effects of weather-related delays. The model predicts the future states of wind turbines, repairs, downtime expenses, failures, and production losses. Simulation results show the optimal scenario for effective intervention and the adaptability of the proposed model in controlling wind farm assets. By considering various maintenance planning approaches, the model identifies the factors affecting maintenance and minimises the impact of human response on O&M activities in OWFs.</p
Phosphorylation of GntR reduces Streptococcus suis oxidative stress resistance and virulence by inhibiting NADH oxidase transcription.
GntR transcription factor of Streptococcus suis serotype 2 (SS2) is a potential substrate protein of STK, but the regulation mechanisms of GntR phosphorylation are still unclear. This study confirmed that STK phosphorylated GntR in vivo, and in vitro phosphorylation experiments showed that STK phosphorylated GntR at Ser-41. The phosphomimetic strain (GntR-S41E) had significantly reduced lethality in mice and reduced bacterial load in the blood, lung, liver, spleen, and brain of infected mice compared to wild-type (WT) SS2. Electrophoretic mobility shift assay (EMSA) and chromatin immunoprecipitation (ChIP) experiments demonstrated that the promoter of nox was bound by GntR. The phosphomimetic protein GntR-S41E cannot bind to the promoter of nox, and the nox transcription levels were significantly reduced in the GntR-S41E mutant compared to WT SS2. The virulence in mice and the ability to resist oxidative stress of the GntR-S41E strain were restored by complementing transcript levels of nox. NOX is an NADH oxidase that catalyzes the oxidation of NADH to NAD+ with the reduction of oxygen to water. We found that NADH is likely accumulated under oxidative stress in the GntR-S41E strain, and higher NADH levels resulted in increased amplified ROS killing. In total, we report GntR phosphorylation could inhibit the transcription of nox, which impaired the ability of SS2 to resist oxidative stress and virulence