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Mishra, M., Martinsson, J., Goebel, K. & Rantatalo, M. (2021). Bearing Life Prediction with Informed Hyperprior Distribution: A Bayesian Hierarchical and Machine Learning Approach. IEEE Access, 9, 157002-157011
Öppna denna publikation i ny flik eller fönster >>Bearing Life Prediction with Informed Hyperprior Distribution: A Bayesian Hierarchical and Machine Learning Approach
2021 (Engelska)Ingår i: IEEE Access, E-ISSN 2169-3536, Vol. 9, s. 157002-157011Artikel i tidskrift (Refereegranskat) Published
Abstract [en]

A Bayesian hierarchical model (BHM) is developed to predict bearing life using envelope acceleration data in combination with a degradation model and prior knowledge of the bearing rating life. The BHM enables the inference of individual bearings, groups of bearings, or bearings operating under certain conditions. The key benefit of the BHM approach is that the relationships between the bearing model parameters and their prior distributions can be expressed at different hierarchical levels. We begin our analysis using a bearing rating life calculation L10h and an estimate of its associated failure time distribution. Realistic variations to constrain our prior distribution of the failure time are then applied before measurements are available. When data become available, estimates more representative of our specific batch and operating conditions are inferred, both on the individual bearing level and the bearing group level. The proposed prognostics methodology can be used in situations with varying amounts of data. The presented BHM approach can also be used to predict the remaining useful life (RUL) of bearings both in situations in which the bearing is considered to be in a healthy state and in situations after a defect has been detected.

Ort, förlag, år, upplaga, sidor
IEEE Robotics and Automation Society, 2021
Nyckelord
Bayesian hierarchical model, bearing life prediction, bearing life rating L10h, probability distribution, prognostics, remaining useful life
Nationell ämneskategori
Sannolikhetsteori och statistik
Forskningsämne
Drift och underhållsteknik; Centrumbildning - SKF-LTU University Technology Cooperation; Tillämpad matematik
Identifikatorer
urn:nbn:se:ltu:diva-68340 (URN)10.1109/ACCESS.2021.3130157 (DOI)000724471400001 ()2-s2.0-85120049117 (Scopus ID)
Projekt
SKF- UTC
Anmärkning

Validerad;2021;Nivå 2;2021-12-03 (johcin)

Tillgänglig från: 2018-04-13 Skapad: 2018-04-13 Senast uppdaterad: 2023-09-05Bibliografiskt granskad
Lemlikchi, S., Martinsson, J., Djelouah, H., Asmani, M. & Carlson, J. E. (2021). Parametric estimation of overlapping echoes reflected from coated media. Applied Acoustics, 178, Article ID 107990.
Öppna denna publikation i ny flik eller fönster >>Parametric estimation of overlapping echoes reflected from coated media
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2021 (Engelska)Ingår i: Applied Acoustics, ISSN 0003-682X, E-ISSN 1872-910X, Vol. 178, artikel-id 107990Artikel i tidskrift (Refereegranskat) Published
Abstract [en]

In this work, a parametric modeling strategy was used to investigate ultrasonic signals reflecting from coated structures. The model parameter vector is defined by the combined model consisting of hard and soft modeling. The hard model describes the overlap with pure delays, reflection and transmission coefficients. The soft model copes with a more realistic case when all ultrasonic losses are included. The estimation procedure follows the maximum likelihood approach and uses the Levenberg–Marquardt algorithm for optimizing the objective function. The tested waveforms were reflected from thermally sprayed Diamalloy 4060 coatings deposited on 310SS substrate with increasing degree of overlapping echoes. Measurements were carried out in pulse-echo mode using a 15 MHz nominal frequency transducer. A good prediction of overlapping signals was achieved. Reverberating coating echoes were successfully separated and coating properties (time-of-flight (TOF), ultrasonic velocity and attenuation) were directly deduced. Results show the potential of the method to investigate overlapping ultrasonic signals reflecting from highly attenuating layers such as thermal sprayed coatings. It also shows the ability for the method to make a complete separation of the overlapping echoes, not only between the substrate and the coating echoes, but also between the reverberations in the coating itself that has been neglected for a long time. This allows an accurate characterization of the coating properties.

Ort, förlag, år, upplaga, sidor
Elsevier, 2021
Nyckelord
Combined model, Overlapping echoes, Parametric estimation, Coated media, Thermally sprayed coatings
Nationell ämneskategori
Matematisk analys Signalbehandling
Forskningsämne
Signalbehandling; Tillämpad matematik
Identifikatorer
urn:nbn:se:ltu:diva-83264 (URN)10.1016/j.apacoust.2021.107990 (DOI)000640183600026 ()2-s2.0-85102044481 (Scopus ID)
Anmärkning

Validerad;2021;Nivå 2;2021-03-15 (alebob)

Tillgänglig från: 2021-03-15 Skapad: 2021-03-15 Senast uppdaterad: 2022-07-11Bibliografiskt granskad
Törnman, W., Martinsson, J. & Dineva, S. (2021). Robust Bayesian estimator for S-wave spectra, using a combined empirical Green’s function. Geophysical Journal International, 227, 403-438, Article ID ggab184.
Öppna denna publikation i ny flik eller fönster >>Robust Bayesian estimator for S-wave spectra, using a combined empirical Green’s function
2021 (Engelska)Ingår i: Geophysical Journal International, ISSN 0956-540X, E-ISSN 1365-246X, Vol. 227, s. 403-438, artikel-id ggab184Artikel i tidskrift (Refereegranskat) Published
Abstract [en]

We propose a new fully automatic and robust Bayesian method to estimate precise and reliable model parameters describing the observed S-wave spectra. All the spectra associated with each event are modelled jointly, using a t-distribution as likelihood function together with informative prior distributions for increased robustness against outliers and extreme values. The model includes the observed noise and a combined empirical Green’s function. It captures source-, receiver-, and path-dependent terms in the description of the observed spectra by combining a physical source and attenuation model with a spatially and event-size dependent empirical compensation. The proposed method propagates estimation uncertainties along the entire processing chain starting from the hypocentre location and delivers reliable uncertainty description of the estimands. The objective is to automatically provide robust and valid descriptions of the observed S-wave spectra generated from an earthquake source in a noisy and heterogeneous environment. The efficiency of the method is tested with synthetic seismograms, and the model is calibrated and cross-validated using 31 640 mining induced seismic events in a iron ore mine (in north of Sweden) with an comprehensive seismic network. The model is evaluated using both posterior predictive checks and residual analysis and we found no evidence that indicates any model deficiencies with respect to central tendency, dispersion, and residual trends.

Ort, förlag, år, upplaga, sidor
Oxford University Press, 2021
Nyckelord
Induced seismicity, Statistical seismology, Probability distributions, Earthquake dynamics
Nationell ämneskategori
Geofysik
Forskningsämne
Gruv- och berganläggningsteknik; Tillämpad fysik
Identifikatorer
urn:nbn:se:ltu:diva-84956 (URN)10.1093/gji/ggab184 (DOI)000697669800006 ()2-s2.0-85112609372 (Scopus ID)
Forskningsfinansiär
VinnovaForskningsrådet FormasEnergimyndigheten
Anmärkning

Validerad;2021;Nivå 2;2021-07-14 (johcin);

Finansiär: Luossavaara-Kiirunavaara AB

Tillgänglig från: 2021-06-07 Skapad: 2021-06-07 Senast uppdaterad: 2022-11-08Bibliografiskt granskad
Shekhar, G., Gustafson, A., Jonsson, K., Martinsson, J. & Schunnesson, H. (2020). Development of an optimal draw control strategy for a sublevel caving operation at Malmberget mine. Mining Technology, 129(2), 104-112
Öppna denna publikation i ny flik eller fönster >>Development of an optimal draw control strategy for a sublevel caving operation at Malmberget mine
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2020 (Engelska)Ingår i: Mining Technology, ISSN 2572-6668, Vol. 129, nr 2, s. 104-112Artikel i tidskrift (Refereegranskat) Published
Abstract [en]

This paper addresses the identification of the optimal draw control strategy for a sublevel caving (SLC) operation at Malmberget mine in Sweden. Two mathematical models, a probability model and an economic model, were created using five datasets: bucket weights, bucket grades, extraction ratio, mine economics parameters and production constraints. The probability model was used to generate a set of simulated bucket weights and corresponding bucket grades which acts as a ‘virtual mine’ environment. The economic model assesses the economic impact of loading at the draw point. Two approaches to draw control were tested using the ‘virtual mine’ created by the probability model. Based on the results of the simulation tests, an optimal draw control strategy is suggested for a field test at the mine. The new draw control strategy optimises further the loading operation at Malmberget mine. The paper shows a roadmap for optimising draw control strategy for SLC operations.

Ort, förlag, år, upplaga, sidor
Taylor & Francis, 2020
Nyckelord
Draw control strategy, optimised underground mining, Load Haul Dump (LHD), sublevel caving (SLC), mine economics, heuristics, process control optimisation
Nationell ämneskategori
Annan samhällsbyggnadsteknik Matematisk analys
Forskningsämne
Gruv- och berganläggningsteknik; Tillämpad matematik
Identifikatorer
urn:nbn:se:ltu:diva-79641 (URN)10.1080/25726668.2020.1775432 (DOI)000546908600005 ()2-s2.0-85087385397 (Scopus ID)
Anmärkning

Validerad;2020;Nivå 2;2020-12-10 (marisr)

Tillgänglig från: 2020-06-16 Skapad: 2020-06-16 Senast uppdaterad: 2020-12-10Bibliografiskt granskad
Martinsson, J. & Törnman, W. (2020). Modelling the Dynamic Relationship Between Mining Induced Seismic Activity and Production Rates, Depth and Size: A Mine-Wide Hierarchical Model. Pure and Applied Geophysics, 177(6), 2619-2639
Öppna denna publikation i ny flik eller fönster >>Modelling the Dynamic Relationship Between Mining Induced Seismic Activity and Production Rates, Depth and Size: A Mine-Wide Hierarchical Model
2020 (Engelska)Ingår i: Pure and Applied Geophysics, ISSN 0033-4553, E-ISSN 1420-9136, Vol. 177, nr 6, s. 2619-2639Artikel i tidskrift (Refereegranskat) Published
Abstract [en]

The dynamic properties of mining induced seismic activity with respect to production rate, depth and size are studied in seven orebodies in the same underground iron ore mine. The objective is to understand the relationship between the measured seismic activity and the: seismic decay time, planned production rate, production size and mining depth. This relationship is the first step to individually customise the production rate for each orebody in the mine, make short-term predictions of future seismicity given planned productions, and to find out in what way the available predictors affect the seismicity. The seismic response with respect to the dependent variables is parametrised and the estimated decay times for each orebody, which are of particular interest here, are compared. An autoregressive model is proposed to capture the dynamic relationship between the induced seismic activity, the current production rate and the past seismic activity. Bayesian estimation of the parameters is considered and parameter constraints are incorporated in the prior distributions. The models for all orebodies are tied together and modelled hierarchically to capture the underlying joint structure of the problem, where the mine-wide parameters are learnt together with the individual orebody parameters from the observed data. Comparisons between the parameters from the hierarchical model and independent models are given. Group-level regressions reveal dependencies on size and mining depth. Model validation with posterior predictive checking using several discrepancy measures could not detect any model deficiencies or flaws. Posterior predictive intervals are evaluated and inference of model parameters are presented.

Ort, förlag, år, upplaga, sidor
Springer, 2020
Nyckelord
Induced seismicity, Bayesian hierarchical model, Probabilistic forecasting, Time-series analysis, Statistical seismology
Nationell ämneskategori
Geofysik Annan samhällsbyggnadsteknik Matematisk analys
Forskningsämne
Gruv- och berganläggningsteknik; Tillämpad matematik
Identifikatorer
urn:nbn:se:ltu:diva-77176 (URN)10.1007/s00024-019-02378-y (DOI)000500622800002 ()2-s2.0-85076109961 (Scopus ID)
Anmärkning

Validerad;2020;Nivå 2;2020-08-17 (johcin)

Tillgänglig från: 2019-12-15 Skapad: 2019-12-15 Senast uppdaterad: 2023-09-06Bibliografiskt granskad
Törnman, W. & Martinsson, J. (2020). Reliable automatic processing of seismic events: solving the Swiss cheese problem. In: Johan Wesseloo (Ed.), Proceedings of the Second International Conference on Underground Mining Technology: . Paper presented at Second International Conference on Underground Mining Technology (UMT2020), Perth, Australia (Online), November 3-4, 2020 (pp. 155-172). University of Western Australia
Öppna denna publikation i ny flik eller fönster >>Reliable automatic processing of seismic events: solving the Swiss cheese problem
2020 (Engelska)Ingår i: Proceedings of the Second International Conference on Underground Mining Technology / [ed] Johan Wesseloo, University of Western Australia , 2020, s. 155-172Konferensbidrag, Publicerat paper (Refereegranskat)
Abstract [en]

BEMIS (Bayesian estimation of mining-induced seismicity) is a fully automatic, near real-time, robust and self-learning seismic processing solution for mining-induced seismic events. A prototype solution is tested in parallel with IMS’s routine manual processing in LKAB’s underground mines in Malmberget and Kiruna, providing four times more accurate earthquake locations based on 290 known blasts, 40 times faster processing time that scales with computer power, and the ability to detect and locate up to six times more events given the same input data. In addition to a fully automatic system, BEMIS provides a variety of unique functions such as quality control of all results, self-learning adaptation and calibrations, tomography, and prediction models of future seismicity. In this paper, we summarise the results from different investigations throughout time and discuss the unique approach considered to obtain reliable auto-processing in a challenging, unknown and changing environment.

Ort, förlag, år, upplaga, sidor
University of Western Australia, 2020
Nyckelord
mining-induced seismicity, automatic processing, statistical seismology, reliable seismic parameters
Nationell ämneskategori
Geofysik
Forskningsämne
Gruv- och berganläggningsteknik; Tillämpad matematik
Identifikatorer
urn:nbn:se:ltu:diva-84953 (URN)10.36487/ACG_repo/2035_04 (DOI)
Konferens
Second International Conference on Underground Mining Technology (UMT2020), Perth, Australia (Online), November 3-4, 2020
Forskningsfinansiär
VinnovaForskningsrådet FormasEnergimyndigheten
Anmärkning

ISBN för värdpublikation: 978-0-9876389-9-1;

Finansiär: Luossavaara-Kiirunavaara AB

Tillgänglig från: 2021-06-07 Skapad: 2021-06-07 Senast uppdaterad: 2023-09-06Bibliografiskt granskad
Lemlikchi, S., Martinsson, J., Hamrit, A., Djelouah, H., Asmani, M. & Carlson, J. E. (2019). Ultrasonic Characterization of Thermally Sprayed Coatings. Journal of thermal spray technology (Print), 28(3), 391-404
Öppna denna publikation i ny flik eller fönster >>Ultrasonic Characterization of Thermally Sprayed Coatings
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2019 (Engelska)Ingår i: Journal of thermal spray technology (Print), ISSN 1059-9630, E-ISSN 1544-1016, Vol. 28, nr 3, s. 391-404Artikel i tidskrift (Refereegranskat) Published
Abstract [en]

This paper describes the simultaneous determination of the ultrasonic parameters in thermally sprayed coatings. The parameters of interest are the longitudinal wave velocity and the ultrasonic attenuation. The test materials are two cobalt-based coatings (FSX 414 and Diamalloy 4060), both deposited onto stainless steel (310SS) substrates. The ultrasonic measurements were carried out in the pulse-echo configuration using several transducers. The ultrasonic signals reflected from the coatings were successfully estimated using the combined model, together with the maximum likelihood estimation and the Levenberg–Marquardt approach. The best estimate was obtained for 20 MHz measurements. Once the model was validated, the ultrasonic parameters of the thermally sprayed coatings were extracted. Model validation is based on the analysis of the residual between measured and estimated signals. Results showed non-dispersive ultrasonic velocities with average values of (3940±50)m/s" role="presentation" style="box-sizing: border-box; display: inline-table; line-height: normal; letter-spacing: normal; word-spacing: normal; overflow-wrap: normal; white-space: nowrap; float: none; direction: ltr; max-width: none; max-height: none; min-width: 0px; min-height: 0px; border: 0px; padding: 0px; margin: 0px; position: relative;">(3940±50)m/s(3940±50)m/s in Diamalloy 4060 and (4260±20)m/s" role="presentation" style="box-sizing: border-box; display: inline-table; line-height: normal; letter-spacing: normal; word-spacing: normal; overflow-wrap: normal; white-space: nowrap; float: none; direction: ltr; max-width: none; max-height: none; min-width: 0px; min-height: 0px; border: 0px; padding: 0px; margin: 0px; position: relative;">(4260±20)m/s(4260±20)m/s in FSX 414. High ultrasonic attenuation with a quadratic frequency dependence was observed for both materials. Moreover, it was found that the ultrasonic parameters in thermally sprayed materials are microstructure dependent. For close densities, the harder the coating, the higher the ultrasonic wave velocity and attenuation.

Ort, förlag, år, upplaga, sidor
Springer, 2019
Nyckelord
combined model, Diamalloy 4060, FSX 414, thermal spray coating, ultrasonic attenuation, ultrasonic wave velocity
Nationell ämneskategori
Signalbehandling Annan elektroteknik och elektronik Sannolikhetsteori och statistik
Forskningsämne
Matematisk statistik; Signalbehandling
Identifikatorer
urn:nbn:se:ltu:diva-72700 (URN)10.1007/s11666-019-00832-w (DOI)000459400600007 ()2-s2.0-85060769510 (Scopus ID)
Anmärkning

Validerad;2019;Nivå 2;2019-02-27 (svasva);

For correction, see: Lemlikchi, S., Martinsson, J., Hamrit, A. et al. Correction to: Ultrasonic Characterization of Thermally Sprayed Coatings. J Therm Spray Tech 28, 591 (2019). https://doi.org/10.1007/s11666-019-00842-8

Tillgänglig från: 2019-01-27 Skapad: 2019-01-27 Senast uppdaterad: 2023-09-07Bibliografiskt granskad
Martinsson, J. & Jonsson, A. (2018). A New Model for the Distribution of Observable Earthquake Magnitudes and Applications to b-Value Estimation. IEEE Geoscience and Remote Sensing Letters, 15(6), 833-837
Öppna denna publikation i ny flik eller fönster >>A New Model for the Distribution of Observable Earthquake Magnitudes and Applications to b-Value Estimation
2018 (Engelska)Ingår i: IEEE Geoscience and Remote Sensing Letters, ISSN 1545-598X, E-ISSN 1558-0571, Vol. 15, nr 6, s. 833-837Artikel i tidskrift (Refereegranskat) Published
Abstract [en]

The b-value in the Gutenberg–Richter (GR) law contains information that is essential for evaluating earthquake hazard and predicting the occurrence of large earthquakes. Estimates of b are often based on seismic events whose magnitude exceed a certain threshold, the so-called magnitude of completeness. Such estimates are sensitive to the choice of threshold and often ignore a substantial portion of available data. We present a general model for the distribution of observable earthquake magnitudes and an estimation procedure that takes all measurements into account. The model is obtained by generalizing previous probabilistic descriptions of sensor network limitations and using a generalization of the GR law. We show that our model is flexible enough to handle spatio-temporal variations in the seismic environment and captures valuable information about sensor network coverage. We also show that the model leads to significantly improved b-value estimates compared with established methods relying on the magnitude of completeness.

Ort, förlag, år, upplaga, sidor
IEEE, 2018
Nationell ämneskategori
Geofysik Sannolikhetsteori och statistik
Forskningsämne
Matematisk statistik
Identifikatorer
urn:nbn:se:ltu:diva-69044 (URN)10.1109/LGRS.2018.2812770 (DOI)000432958000007 ()2-s2.0-85044388582 (Scopus ID)
Anmärkning

Validerad;2018;Nivå 2;2018-06-05 (rokbeg)

Tillgänglig från: 2018-06-01 Skapad: 2018-06-01 Senast uppdaterad: 2018-09-14Bibliografiskt granskad
Mishra, M., Martinsson, J., Rantatalo, M. & Goebel, K. (2018). Bayesian hierarchical model-based prognostics for lithium-ion batteries. Reliability Engineering & System Safety, 172, 25-35
Öppna denna publikation i ny flik eller fönster >>Bayesian hierarchical model-based prognostics for lithium-ion batteries
2018 (Engelska)Ingår i: Reliability Engineering & System Safety, ISSN 0951-8320, E-ISSN 1879-0836, Vol. 172, s. 25-35Artikel i tidskrift (Refereegranskat) Published
Abstract [en]

To optimise operation and maintenance, knowledge of the ability to perform the required functions is vital. The ability is governed by the usage of the system (operational issues) and availability aspects like reliability of different components. This paper proposes a Bayesian hierarchical model (BHM)-based prognostics approach applied to Li-ion batteries, where the goal is to analyse and predict the discharge behaviour of such batteries with variable load profiles and variable amounts of available discharge data. The BHM approach enables inferences for both individual batteries and groups of batteries. Estimates of the hierarchical model parameters and the individual battery parameters are presented, and dependencies on load cycles are inferred. A BHM approach where the operational and reliability aspects end of life (EoD) and end of life (EoL) is studied where its shown that predictions of EoD can be made accurately with a variable amount of battery data. Without access to measurements, e.g. predicting a new battery, the predictions are based only on the prior distributions describing the similarity within the group of batteries and their dependency on the load cycle. A discharge cycle dependency can also be identified in the result giving the opportunity to predict the battery reliability.

Ort, förlag, år, upplaga, sidor
Elsevier, 2018
Nyckelord
Bayesian hierarchical model, Prognostics, End of discharge, Lithium-ion battery
Nationell ämneskategori
Annan samhällsbyggnadsteknik Sannolikhetsteori och statistik
Forskningsämne
Drift och underhållsteknik; Matematisk statistik
Identifikatorer
urn:nbn:se:ltu:diva-66884 (URN)10.1016/j.ress.2017.11.020 (DOI)000424960000003 ()2-s2.0-85037540599 (Scopus ID)
Anmärkning

Validerad;2018;Nivå 2;2017-12-14 (andbra)

Tillgänglig från: 2017-12-04 Skapad: 2017-12-04 Senast uppdaterad: 2023-09-05Bibliografiskt granskad
Jonsson, K. & Martinsson, J. (2018). Evaluating the effect on seismicity of a hydraulic fracturing trial using Bayesian data analysis. In: Y Potvin, J Jakubec (Ed.), Caving 2018: Proceedings of the Fourth International Symposium on Block and Sublevel Caving. Paper presented at Fourth International Symposium on Block and Sublevel Caving (Caving 2018), 15-17 October, 2018, Vancouver, Canada (pp. 451-658). Australian Centre for Geomechanics
Öppna denna publikation i ny flik eller fönster >>Evaluating the effect on seismicity of a hydraulic fracturing trial using Bayesian data analysis
2018 (Engelska)Ingår i: Caving 2018: Proceedings of the Fourth International Symposium on Block and Sublevel Caving / [ed] Y Potvin, J Jakubec, Australian Centre for Geomechanics, 2018, s. 451-658Konferensbidrag, Publicerat paper (Refereegranskat)
Abstract [en]

During the summer of 2017, a hydraulic fracturing trial was performed in the crown pillar of one of the orebodies in LKAB’s mine in Malmberget. Mucking in the orebody beneath the crown pillar recommenced in September 2017, after being shut down since April 2015. The mucking was shut down in 2015 because a number of large seismic events had caused significant disturbances in the nearby town, with vibration up to 35 mm/s. A research project was started with the final goal to start up production again with less disturbance to the town. Hydraulic fracturing was determined to be an interesting method for improving caveability of the crown pillar, and a trial was set up. The trial consisted of partially fracturing three boreholes drilled from the ground surface into the crown pillar, which is between 550 and 650 m thick at the trial location. Hydraulic fractures were placed with 2.5 m spacing at the bottom 50 m of each hole. As part of the evaluation of the effectiveness of the trial, the seismicity before and after the hydraulic fracturing trial has been compared using standard Bayesian techniques to infer differences. The analysis show a difference in b-value before and after the trial, which is demonstrated by the parameter 𝛥b having a positive value. The 95% high density interval (HDI) of 𝛥b excludes the value of zero, which gives confidence in the conclusion. The difference in b-value depends on the choice of magnitude of completeness, so it is recommended that the analysis is repeated with a method using all recorded events, i.e. using the full dataset.

Ort, förlag, år, upplaga, sidor
Australian Centre for Geomechanics, 2018
Nyckelord
hydraulic fracturing, seismicity, Bayesian data analysis
Nationell ämneskategori
Matematisk analys
Forskningsämne
Tillämpad matematik
Identifikatorer
urn:nbn:se:ltu:diva-77175 (URN)10.36487/ACG_rep/1815_50_Jonsson (DOI)
Konferens
Fourth International Symposium on Block and Sublevel Caving (Caving 2018), 15-17 October, 2018, Vancouver, Canada
Anmärkning

ISBN för värdpublikation: 978-0-9924810-9-4

Tillgänglig från: 2019-12-15 Skapad: 2019-12-15 Senast uppdaterad: 2020-09-10Bibliografiskt granskad
Organisationer
Identifikatorer
ORCID-id: ORCID iD iconorcid.org/0000-0002-6289-4949

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