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1. Industry-specific impacts of global drivers in the European Arctic.

Author

Nygaard, V., Engen, S., Suopajärvi, L., Edvardsdóttir, A.G., Iversen, A., Bogadóttir, R., Tuulentie, S., Bjerke, J.W., Rautio, P., Elomina, J., and Miettinen, J.

Abstract

Natural resource-based industries in the European Arctic operate in an increasingly competitive and globalized Arctic. Knowledge of key drivers and their industrial impacts provide industries, companies, communities, and decision-makers at multiple levels with information on how to plan, manage and collaborate for the future. In this study, we explore the global drivers that affect key industries in the European Arctic – aquaculture, forestry, mining and tourism – and what impacts these drivers have on the specific industries. The study identifies eight common global drivers affecting all four industries, after applying thematic analysis of an extensive interview material with national industrial specialists in the European Arctic countries and at EU level. The global drivers identified, impact the development of key industries in the European Arctic differently and point to context-specific developments as well as a considerable uncertainty what the future holds. [ABSTRACT FROM AUTHOR]

Published
2024
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6. Gradient boosted regression trees for modelling onset of austenite decomposition during cooling of steels

Author

Luukkonen, J. (Juho), Pohjonen, A. (Aarne), Louhenkilpi, S. (Seppo), Miettinen, J. (Jyrki), Sillanpää, M. J. (Mikko J.), Laitinen, E. (Erkki), Luukkonen, J. (Juho), Pohjonen, A. (Aarne), Louhenkilpi, S. (Seppo), Miettinen, J. (Jyrki), Sillanpää, M. J. (Mikko J.), and Laitinen, E. (Erkki)

Abstract

Continuous cooling transformation (CCT) diagrams can be constructed by empirical methods, which is expensive and time consuming, or by fitting a model to available experimental data. Examples of data-driven models implemented so far include regression models, artificial neural networks, k-Nearest Neighbours and Random Forest. Gradient boosting machine (GBM) has been succesfully used in many machine learning applications, but has not been used before in modelling CCT-diagrams. This article presents a novel way of predicting ferrite start temperatures for low alloyed steels using gradient boosting. First, transformation onset temperatures are predicted over a grid of values with a trained GBM-model after which a physically-based model is fitted to the piecewise constant curve obtained as output from the model. Predictability of the GBM-model is tested with two sets of CCT-diagrams and compared to Random Forest and JMatPro software. GBM outperforms its competitors under all tested model performance metrics: e.g. R² for test data is 0.92, 0.87 and 0.70 for GBM, Random Forest and JMatPro respectively. Output from the GBM-model is used for fitting a physically based model, which enables the estimation of transformation start for any linear or nonlinear cooling path. This can be further converted to Time-Temperature-Transformation (TTT) diagram.

Published
2023

9. Whitening CNN-Based Rotor System Fault Diagnosis Model Features

Author

Miettinen, J. (Jesse), Nikula, R.-P. (Riku-Pekka), Keski-Rahkonen, J. (Joni), Fagerholm, F. (Fredrik), Tiainen, T. (Tuomas), Sierla, S. (Seppo), Viitala, R. (Raine), Mechatronics, University of Oulu, Kongsberg Maritime Finland, Department of Electrical Engineering and Automation, Department of Mechanical Engineering, Aalto-yliopisto, and Aalto University

Subjects
MACHINE, intelligent fault diagnosis, CNN architecture, normalization techniques, vibration, CONVOLUTIONAL NEURAL-NETWORK, DEEP LEARNING-MODEL
Abstract

Intelligent fault diagnosis (IFD) models have the potential to increase the level of automation and the diagnosis accuracy of machine condition monitoring systems. Many of the latest IFD models rely on convolutional layers for feature extraction from vibration data. The majority of these models employ batch normalisation (BN) for centring and scaling the input for each neuron. This study includes a novel examination of a competitive approach for layer input normalisation in the scope of fault diagnosis. Network deconvolution (ND) is a technique that further decorrelates the layer inputs reducing redundancy among the learned features. Both normalisation techniques are implemented on three common 1D-CNN-based fault diagnosis models. The models with ND mostly outperform the baseline models with BN in three experiments concerning fault datasets from two different rotor systems. Furthermore, the models with ND significantly outperform the baseline models with BN in the common CWRU bearing fault tests with load domain shifts, if the data from drive-end and fan-end sensors are employed. The results show that whitened features can improve the performance of CNN-based fault diagnosis models.

Published
2022

10. Simulation of the solidification and microstructural evolution in steel casting processes using the InterDendritic Solidification tool

Author

Miettinen, J. (Jyrki), Somani, M. (Mahesh), Visuri, V.-V. (Ville-Valtteri), Koskenniska, S. (Sami), Louhenkilpi, S. (Seppo), Fabritius, T. (Timo), Kömi, J. (Jukka), Miettinen, J. (Jyrki), Somani, M. (Mahesh), Visuri, V.-V. (Ville-Valtteri), Koskenniska, S. (Sami), Louhenkilpi, S. (Seppo), Fabritius, T. (Timo), and Kömi, J. (Jukka)

Abstract

InterDendritic Solidification (IDS) is a thermodynamic–kinetic software combined with a microstructure tool developed to simulate the nonequilibrium solidification (non-EQS) of steels. Herein, its main calculation module, solidification (SOL), is introduced, and some essential results of that module, such as the formation of ferrite and austenite in different types of steels during their solidification, and the formation and dissolution of precipitates during subsequent cooling and heating processes, respectively, following solidification, are presented. The non-EQS is compared with equilibrium and poor-kinetics solidification to demonstrate the effect of kinetics on the results using finite solute diffusion and microstructure data. The poor-kinetics solidification is comparable with the modified Scheil simulation ignoring the solid-state diffusion of slowly moving metallic elements. A particular emphasis is made on demonstrating how to use a postprocessing treatment to control the residual ferrite amounts in stainless steels and the extent of precipitation in particular steel. In this context, the phenomena occurring behind the results are discussed. Finally, to validate the simulations of the SOL module, its calculations are compared with numerous solidification measurements, such as the liquidus and solidus temperatures of different steels and the residual ferrite amounts in stainless steels.

Published
2022

12. P405: INHIBITION OF CKS1-DEPENDENT PROTEOSTASIS REVEALS VULNERABILITIES IN LEUKAEMIC STEM CELLS WITH CONCOMITANT PROTECTION OF HEALTHY HAEMATOPOIETIC STEM CELLS

Author

Grey, W., primary, Rio-Machin, A., additional, Casado-Izquierdo, P., additional, Gronroos, E., additional, Ali, S., additional, Miettinen, J., additional, Bewicke-Copley, F., additional, Parsons, A., additional, Heckman, C., additional, Swanton, C., additional, Cutillas, P., additional, Gribben, J., additional, Fitzgibbon, J., additional, and Bonnet, D., additional

Published
2022
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17. Carbon-containing thermodynamic descriptions of the Fe–Cr–Cu–Mo–Ni–C system for modeling the solidification of steels

Author

Miettinen, J. (Jyrki), Visuri, V.-V. (Ville-Valtteri), and Fabritius, T. (Timo)

Subjects
Fe–Cr–Cu–Mo–Ni–C system, thermodynamics, jähmettyminen, termodynamiikka, steels, teräs, solidification, Fe–Cr–Cu–Mo–Ni–C –systeemi
Abstract

The thermodynamic Iron Alloy Database (IAD) has been developed since 2000 to provide consistent thermodynamic data for modeling the solidification of steels. This work presents the carbon containing thermodynamic descriptions of the Fe–Cr–Cu–Mo–Ni–C system, extending the two earlier publications on that database. The results suggest a good agreement of the thermodynamic descriptions with measured data. Tiivistelmä Vuodesta 2000 lähtien on kehitetty rautapohjaisten seosten termodynaamista datakantaa (Iron Alloy Database, IAD), jonka tarkoituksena on tuottaa yksinkertaista ja konsistenttia termodynaamista dataa terästen jähmettymisen mallintamiseen. Tämä työ esittelee systeemin Fe–Cr–Cu–Mo–Ni–C alikuvaukset hiilen osalta. Kuvaukset laajentavat aiemmissa tutkimuksissa esitetyistä Fe–Al–Mn–Si–C ja Fe–Al–Cr–Cu–Mn–Mo–Ni–Si kuvauksista luotua IAD-datakantaa. Tulokset osoittavat termodynaamisten kuvausten vastaavan hyvin mitattua aineistoa.

Published
2021

19. Thermodynamic description of ternary Fe–B–X systems. Part 9:Fe-B-Cu

Author

Miettinen, J. (Jyrki), Visuri, V.-V. (Ville-Valtteri), and Fabritius, T. (Timo)

Subjects
Fe-B-X systems, Fe-B-Cu system, Fe-based systems, thermodynamic database, phase diagrams, thermodynamic modelling
Abstract

Thermodynamic descriptions of the ternary Fe-B-Cu system and its binary sub-system B-Cu aredeveloped in the context of a new Fe-B-X (X = Cr, Cu, Mn, Mo, Ni, Si, Ti, V, C) database. The thermodynamic parameters of the other binary sub-systems (Fe-B and Fe-Cu) are taken from earlier assessments. Experimental thermodynamic and phase equilibrium data available in the literature have been used for the optimization of the Fe-B-Cu and B-Cu systems’ thermodynamic parameters. The solution phases are described using a substitutional solution model and the compounds (two borides of the Fe-B system) are treated as stoichiometric phases. A good agreement was obtained between the calculated and the experimental thermodynamic and phase equilibrium data.

Published
2021

20. Optimization of the CCT curves for steels containing Al, Cu and B

Author

Miettinen, J. (Jyrki), Koskenniska, S. (Sami), Somani, M. (Mahesh), Louhenkilpi, S. (Seppo), Pohjonen, A. (Aarne), Larkiola, J. (Jari), Kömi, J. (Jukka), Miettinen, J. (Jyrki), Koskenniska, S. (Sami), Somani, M. (Mahesh), Louhenkilpi, S. (Seppo), Pohjonen, A. (Aarne), Larkiola, J. (Jari), and Kömi, J. (Jukka)

Abstract

New continuous cooling transformation (CCT) equations have been optimized to calculate the start temperatures and critical cooling rates of phase formations during austenite decomposition in low-alloyed steels. Experimental CCT data from the literature were used for applying the recently developed method of calculating the grain boundary soluble compositions of the steels for optimization. These compositions, which are influenced by solute microsegregation and precipitation depending on the heating/cooling/holding process, are expected to control the start of the austenite decomposition, if initiated at the grain boundaries. The current optimization was carried out rigorously for an extended set of steels than used previously, besides including three new solute elements, Al, Cu and B, in the CCT-equations. The validity of the equations was, therefore, boosted not only due to the inclusion of new elements, but also due to the addition of more low-alloyed steels in the optimization. The final optimization was made with a mini-tab tool, which discarded statistically insignificant parameters from the equations and made them prudently safer to use. Using a thermodynamic-kinetic software, IDS, the new equations were further validated using new experimental CCT data measured in this study. The agreement is good both for the phase transformation start temperatures as well as the final phase fractions. In addition, IDS simulations were carried out to construct the CCT diagrams and the final phase fraction diagrams for 17 steels and two cast irons, in order to outline the influence of solute elements on the calculations and their relationship with literature recommendations.

Published
2021

22. Chromium-, copper-, molybdenum-, and nickel-containing thermodynamic descriptions of the Fe–Al– Cr–Cu–Mn–Mo–Ni–Si system for modeling the solidification of steels

Author

Miettinen, J. (Jyrki), Visuri, V.-V. (Ville-Valtteri), and Fabritius, T. (Timo)

Subjects
thermodynamics, Fe–Al–Cr–Cu–Mn–Mo–Ni–Si system, jähmettyminen, termodynamiikka, steels, teräs, Fe–Al–Cr–Cu–Mn–Mo–Ni–Si –systeemi, solidification
Abstract

The Thermodynamic Iron Alloy Database (IAD) has been developed since 2000 to provide consistent thermodynamic data for modeling solidification of steels. This work presents the chromium, copper, molybdenum and nickel containing thermodynamic descriptions of the Fe–Al–Cr–Cu–Mn–Mo–Ni–Si system, extending the earlier published Fe–Al–Mn–Si–C description of that database. The results suggest a good agreement of the thermodynamic descriptions with the measured data. Tiivistelmä Vuodesta 2000 lähtien on kehitetty rautapohjaisten seosten termodynaamista datakantaa, IAD, jonka tarkoituksena on tuottaa yksinkertaista ja konsistenttia termodynaamista dataa terästen jähmettymisen mallintamiseen. Tämä työ esittelee systeemin Fe–Al–Cr– Cu–Mn–Mo–Ni–Si alikuvaukset kromin, kuparin, molybdeenin ja nikkelin osalta. Kuvaukset laajentavat aiemmassa tutkimuksessa esitetystä Fe–Al–Mn–Si–C -systeemin kuvauksesta luotua IAD-datakantaa. Tulokset osoittavat termodynaamisten kuvausten vastaavan hyvin mitattua aineistoa.

Published
2020

23. Stakeholder and Requirements Assessment Report : Copernicus evolution – Mission Exploitation Concepts Capacity for Copernicus REDD+ and Forest Monitoring Services

Author

Carter, S.L., Herold, M., Achard, F., Ballhorn, Uwe, Gomez, Sharon, Hame, T., Huge, Justine, Langner, Andreas, Miettinen, J., Navratil, Peter, Rauste, Yrjö, Sannier, Christophe, and Haeusler, Thomas

Subjects
Laboratory of Geo-information Science and Remote Sensing, Life Science, Laboratorium voor Geo-informatiekunde en Remote Sensing, PE&RC
Published
2020

24. Thermodynamic description of ternary Fe–B–X systems:part 7: Fe–B–C

Author

Miettinen, J. (J.), Visuri, V.-V. (V.-V.), Fabritius, T. (T.), and Vassilev, G. (G.)

Subjects
Fe-B-X systems, thermodynamic database, Fe-B-C system, phase diagrams, thermodynamic modelling
Abstract

Thermodynamic description of the Fe-B-C system in its iron-rich corner is developed in the context of a new Fe-B-X (X = Cr, Ni, Mn, Si, Ti, V, C) database. The thermodynamic parameters of the binary sub-systems, Fe-B, Fe-C and B-C, are taken from earlier assessments modifying the B-C description. The parameters of the Fe-B-C system are optimized in this study using experimental thermodynamic and phase equilibrium data from the literature. Liquid, beta-rhombo-B and graphite phases are described using the substitutional solution model, while the ferrite (bcc), the austenite (fcc), the cementite (M₃C) and the M₂₃C₆ phases are described with the sublattice model and the borides, Fe₂B, FeB and B₄C, are treated as stoichiometric phases. A good correlation was obtained between the calculated and the experimental thermodynamic and phase equilibrium data. The description is recommended to be used at the composition region of wt% C + wt% B < 15 and at temperatures below 2700oC.

Published
2020

25. Thermodynamic description of ternary Fe–B–X systems. Part 8:Fe–B–Mo, with extension to quaternary Fe–B–Cr–Mo system

Author

Miettinen, J. (Jyrki), Visuri, V.-V. (Ville-Valtteri), and Fabritius, T. (Timo)

Subjects
Fe-B-Mo system, Fe-B-X systems, Fe-based systems, thermodynamic modeling, thermodynamic database, phase diagrams, Fe-B-Cr-Mo system
Abstract

Thermodynamic optimizations of the ternary Fe-B-Mo system and its binary sub-system B-Mo are presented. The Fe-B-Mo description is then extended to the quaternary Fe-B-Cr-Mo system by assessing the ternary B-Cr-Mo system. The thermodynamic descriptions of the other binaries (Fe-B, Fe-Cr, Fe-Mo, B-Cr, and Cr-Mo) and the other ternaries (Fe-B-Cr and Fe-Cr-Mo) are taken from earlier studies. In this study, the adjustable parameters of the B-Mo, Fe-B-Mo, and B-Cr-Mo systems were optimized using the experimental thermodynamic and the phase equilibrium data from the literature. The solution phases of the system (liquid, bcc and fcc) are described with the substitutional solution model, and most borides are treated as stoichiometric phases or semistoichiometric phases, using a simple two-sublattice model for the latter. The system’s intermetallic phases, Chi, Mu, R, and Sigma (not dissolving boron) as well as boride M₃B₂, based on a formulation of (Cr,Fe)(Cr,Fe,Mo)₂(B)₂, are described with a three-sublattice model. Reasonable agreement is obtained between the calculated and measured phase equilibria in all four systems: B-Mo; Fe-B-Mo; B-Cr-Mo; and Fe-B-Cr-Mo.

Published
2020

26. New phenomenological quality criteria for continuous casting of steel based on solidification and microstructure tool IDS

Author

Louhenkilpi, S. (Seppo), Miettinen, J. (Jyrki), Visuri, V.-V. (Ville-Valtteri), Somani, M. C. (Mahesh C.), Koskenniska, S. (Sami), Fabritius, T. (Timo), Louhenkilpi, S. (Seppo), Miettinen, J. (Jyrki), Visuri, V.-V. (Ville-Valtteri), Somani, M. C. (Mahesh C.), Koskenniska, S. (Sami), and Fabritius, T. (Timo)

Abstract

The aim of this work was to derive new quality criteria based on steel composition and cooling pattern for continuous casting and for the subsequent cooling and reheating processes. The criteria were devised based on the outputs of multiphysics simulation tools for casting applications. The criteria were found to be good predictors of whether a steel grade combined with a given cooling pattern is prone to a specific defect. The criteria are useful in providing a theoretical justification as to why certain defects form or would form, and can be used for devising practical solutions to avoid them. In practice, the final determination of whether a defect will form depends on the cumulative impact of various single quality criteria combined with the models/data describing the developing mechanical and thermal stresses. In this paper, new quality criteria are proposed for different kinds of cracking-related and gas defects along with case examples.

Published
2020

27. Thermodynamic, kinetic, and microstructure data for modeling solidification of Fe-Al-Mn-Si-C alloys

Author

Miettinen, J. (Jyrki), Koskenniska, S. (Sami), Visuri, V.-V. (Ville-Valtteri), Somani, M. (Mahesh), Fabritius, T. (Timo), Kömi, J. (Jukka), Miettinen, J. (Jyrki), Koskenniska, S. (Sami), Visuri, V.-V. (Ville-Valtteri), Somani, M. (Mahesh), Fabritius, T. (Timo), and Kömi, J. (Jukka)

Abstract

In this study, a set of thermodynamic, kinetic, and microstructure data is presented to simulate the non-equilibrium solidification of Fe-Al-Mn-Si-C alloys. The data were further validated with the experimental measurements and then used in a thermodynamic–kinetic software, IDS, to establish the effect of the alloying and cooling rate on the solidification behavior of high-AlMnSi (Al ≥ 0.5 wt pct, Mn ≥ 2 wt pct, Si ≥ 1 wt pct) steels. The modeling results were additionally validated by conducting electron probe microanalysis (EPMA) measurements. The results reveal that (1) solidification in high-AlMnSi steels occurs at much lower temperatures than in carbon steels; (2) increasing the cooling rate marginally lowers the solidus; (3) the microsegregation of Mn in austenite is much stronger than that of Si and Al due to the tendency of Al and Si to deplete from the liquid phase; (4) the residual delta ferrite content may be influenced by a proper heat treatment but not to the extent that could be expected solely from thermodynamic calculations; (5) in high-AlMnSi steels containing less than 0.2 wt pct carbon, the cracking tendency related to the strengthening above the solidus and the shell growth below the solidus may be much lower than in carbon steels.

Published
2020

32. Thermodynamic description of the Fe–Al–Mn–Si–C system for modelling solidification of steels

Author

Miettinen, J. (Jyrki), Visuri, V.-V. (Ville-Valtteri), and Fabritius, T. (Timo)

Subjects
thermodynamics, jähmettyminen, termodynamiikka, Fe–Al–Mn–Si–C system, steels, teräs, solidification, Fe–Al–Mn–Si–C-systeemi
Abstract

Advanced high-strength (AHS) steels containing aluminium, manganese, silicon and carbon have widely been studied for automotive applications. It is particularly important to know their solidification behaviour and final structure after the austenite decomposition process. A thermodynamic database named the Iron Alloy Database (IAD) has been developed to provide consistent thermodynamic data for the purpose of simulating the solidification of steels. This work presents a thermodynamic assessment of the Fe–Al–Mn–Si–C system and 19 subsystems. The results suggest a good agreement between thermodynamic descriptions and the measured data. Tiivistelmä Alumiinia, mangaania, piitä ja hiiltä sisältäviä kehittyneitä suurlujuusteräksiä on tutkittu runsaasti autoteollisuuden sovelluskohteiden näkökulmasta. Erityisen mielenkiinnon kohteena on niiden jähmettyminen ja lopullinen rakenne austeniitin hajoamisprosessin jälkeen. Termodynaaminen Iron Alloys Database (IAD) -tietokanta on kehitetty tuottamaan konsistenttia termodynaamista dataa terästen jähmettymisen simulointiin. Tämä työ esittelee Fe–Al–Mn–Si–C -systeemin ja 19 alisysteemin termodynaamisen arvioinnin. Tulokset osoittavat, että termodynaamiset kuvaukset vastaavat mitattua aineistoa.

Published
2019

33. Review Assessment for Forest Monitoring Capacity : Horizon 2020 LC-SPACE-02-EO-2018: Copernicus evolution – Mission Exploitation Concepts Capacity for Copernicus REDD+ and Forest Monitoring Services

Author

Carter, S.L., Herold, M., Achard, F., Ballhorn, Uwe, Desclee, Baudouin, Enssle, F., Eva, H., Navratil, Peter, Gomez, Sharon, Huge, Justine, Langner, Andreas, Miettinen, J., Rauste, Yrjö, Sannier, Christophe, Stibig, H.J., and Haeusler, Thomas

Subjects
Laboratory of Geo-information Science and Remote Sensing, Life Science, Laboratorium voor Geo-informatiekunde en Remote Sensing, PE&RC
Published
2019

34. Thermodynamic description of ternary Fe-B-X systems. Part 4:Fe-B-V

Author

Miettinen, J. (J.), Visuri, V.-V. (V-V.), Fabritius, T. (T.), Milcheva, N. (N.), and Vassilev, G. (G.)

Subjects
Fe-B-V system, Fe-based systems, Fe-B-X systems thermodynamic database, phase diagrams, thermodynamic modelling
Abstract

Thermodynamic descriptions of the ternary Fe-B-V system and its binary sub-system B-V, are developed using experimental thermodynamic and phase equilibrium data from the literature. The thermodynamic parameters of the other binaries, Fe-V and Fe-B, are taken from earlier assessments slightly modifying the Fe-V description. The work is in the context of a new Fe-B-X (X = Cr, Ni, Mn, V, Si, Ti, C) database. The solution phases are described using substitutional solution model. The borides are treated as stoichiometric or semi-stoichiometric phases and described with two-sublattice models.

Published
2019

35. Thermodynamic description of ternary Fe–B–X systems. Part 6:Fe–B–Ti

Author

Miettinen, J. (J.), Visuri, V.-V. (V-V.), Fabritius, T. (T.), Milcheva, N. (N.), and Vassilev, G. (G.)

Subjects
thermodynamic modeling, Fe-B-X systems thermodynamic database, Fe based systems, phase diagrams, Fe-B-Ti system
Abstract

Thermodynamic optimizations of the ternary Fe-B-Ti system and its binary sub-system, B-Ti are presented. The thermodynamic descriptions of the other binaries, Fe-Ti and Fe-B, are taken from the earlier studies slightly modifying the Fe-Ti system assessment. The adjustable parameters of the Fe-B-Ti and B-Ti systems are optimized in this study using the experimental thermodynamic and the phase equilibrium data from the literature. The solution phases of the system are described using the substitutional solution model and the compounds (including borides) are treated as stoichiometric phases. The results show a good correlation between the calculated and measured thermodynamic and phase equilibrium data.

Published
2019

36. Thermodynamic description of ternary Fe–B–X systems. Part 5:Fe–B–Si

Author

Miettinen, J. (J.), Visuri, V.-V. (V-V.), Fabritius, T. (T.), Milcheva, N. (N.), and Vassilev, G. (G.)

Subjects
thermodynamic modeling, Fe-B-Si system, Fe-B-X systems thermodynamic database, Fe based systems, phase diagrams
Abstract

Thermodynamic descriptions of the ternary Fe-B-Si system and its binary sub-system, B-Si, are developed in the context of a new Fe-B-X (X = Cr, Ni, Mn, V, Si, Ti, C) database. The thermodynamic parameters of the other binary sub-systems, Fe-Si and Fe-B, are taken from earlier assessments. Experimental thermodynamic and phase equilibrium data available in the literature has been used for the optimization of the thermodynamic parameters of the Fe-B-Si and B-Si systems. The solution phases are described using substitutional solution model and the compounds (silicides and borides) are treated as stoichiometric phases. The calculated and experimental thermodynamic and phase equilibrium data were found to be in good agreement.

Published
2019

37. Workshop Report: Inventory of State-of-the-Art Technical Capacities in Europe for FM Capacities and Infrastructure : Copernicus evolution – Mission Exploitation Concepts Capacity for Copernicus REDD+ and Forest Monitoring Services

Author

Carter, S.L., Achard, F., Huge, Justine, Langner, Andreas, Miettinen, J., Navratil, Peter, Sannier, Christophe, and Haeusler, Thomas

Subjects
Laboratory of Geo-information Science and Remote Sensing, Life Science, Laboratorium voor Geo-informatiekunde en Remote Sensing, PE&RC
Published
2019

38. Optimization of CCT equations using calculated grain boundary soluble compositions for the simulation of austenite decomposition of steels

Author

Miettinen, J. (Jyrki), Koskenniska, S. (Sami), Somani, M. (Mahesh), Louhenkilpi, S. (Seppo), Pohjonen, A. (Aarne), Larkiola, J. (Jari), Kömi, J. (Jukka), Miettinen, J. (Jyrki), Koskenniska, S. (Sami), Somani, M. (Mahesh), Louhenkilpi, S. (Seppo), Pohjonen, A. (Aarne), Larkiola, J. (Jari), and Kömi, J. (Jukka)

Abstract

New CCT equations have been developed and optimized to simulate the start temperatures of the austenite decomposition process in low-alloyed steels using experimental CCT data published in the literature. Exceptionally, this optimization does not apply the nominal compositions of the steels, but the corresponding soluble compositions of the grain boundaries calculated using IDS software, depending on the reported austenitization treatments of the steels. These compositions, rather than the nominal ones, are expected to control the start of the austenite decomposition, which usually initiates at the grain boundaries. The new optimization treatment takes into account the solute microsegregation and the possible precipitate formation. Using IDS software, the new equations were validated with new experimental CCT data. Agreement was good not only for the austenite decomposition start temperatures, but also for the final phase fractions, indicating fairly reasonable predictions of phase transformation kinetics by the IDS. In addition, IDS simulations were compared with the experimental CCT data of five high-carbon steels, applying both the new equations based on grain boundary soluble compositions as well as the equations based on the nominal compositions. With the same experimental CCT data used in optimization, better agreement was obtained with the new equations, indicating the importance of determining the soluble compositions at the grain boundaries where the austenite decomposition process is likely to begin.

Published
2019

39. Online modelling of heat transfer, solidification and microstructure in continuous casting of steel

Author

Louhenkilpi, S. (S.), Miettinen, J. (J.), Laine, J. (J.), Vesanen, R. (R.), Rentola, I. (I.), Moilanen, J. (J.), Visuri, V.-V. (V-V.), Heikkinen, E.-P. (E-P.), Jokilaakso, A. (A.), Louhenkilpi, S. (S.), Miettinen, J. (J.), Laine, J. (J.), Vesanen, R. (R.), Rentola, I. (I.), Moilanen, J. (J.), Visuri, V.-V. (V-V.), Heikkinen, E.-P. (E-P.), and Jokilaakso, A. (A.)

Abstract

Advanced numerical simulation models for continuous casting of steel were developed in Finland by Casim Consulting and Aalto University in cooperation with the University of Oulu and the steel industry. The aim was to develop models that are scientifically rigorous, but also computationally fast enough to be used in online applications. The models developed are a transient three-dimensional heat transfer model, CastManager, and a solidification and microstructure model, IDS. The computing time of these models are short, and they are integrated together in one online concept. This concept is installed in the automation systems of four slab casters in Finland. Testing and validation work is in progress. The system simulates the important heat transfer, solidification and microstructural phenomena in continuous casting online. The future aim is that this information will be used for online quality control and for optimizing the process conditions to avoid formation of defects. Many quality indices have already been developed. A steady state version of the CastManager tool has also been developed, called Tempsimu.

Published
2019

41. Could continuous cover forestry be an economically and environmentally feasible management option on drained boreal peatlands?

Author

Nieminen, M., Hökkä, H., Laiho, R., Juutinen, A., Ahtikoski, A., Pearson, M., Kojola, S., Sarkkola, S., Launiainen, S., Valkonen, S., Penttilä, T., Lohila, A., Saarinen, M., Haahti, K., Makipää, R., Miettinen, J., Ollikainen, M., Department of Economics and Management, Markku Ollikainen / Principal Investigator, and Environmental and Resource Economics

Subjects
NORTHERN FINLAND, 4112 Forestry, ECOSYSTEM SERVICES, SEEDLING ESTABLISHMENT, SITE PREPARATION, GHG fluxes, Tree growth, Water quality, NORWAY SPRUCE FORESTS, SCOTS PINE STANDS, Regeneration, DISSOLVED ORGANIC-CARBON, Forest economics, Silviculture, SOUTHERN FINLAND, DITCH NETWORK MAINTENANCE, PHOSPHORUS EXPORT
Abstract

Environmental and economic performance of forestry on drained peatlands was reviewed to consider whether continuous cover forestry (CCF) could be a feasible alternative to even-aged management (EM). CCF was regarded feasible particularly because continuously maintaining a tree stand with significant transpiration and interception capacity would decrease the need for ditch network maintenance. Managing CCF forests in such a way that the ground water levels are lower than in clear-cut EM forests but higher than in mature EM forests could decrease greenhouse gas emissions and negative water quality impacts caused both by anoxic redox reactions and oxidation and mineralization of deep peat layers. Regeneration studies indicated potential for satisfactory natural regeneration under CCF on drained peatlands. An economic advantage in CCF over EM is that fewer investments are needed to establish the forest stand and sustain its growth. Thus, even if the growth of trees in CCF forests were lower than in EM forests, CCF could at least in some peatland sites turn out to be a more profitable forest management regime. An advantage of CCF from the viewpoint of socially optimal forest management is that it plausibly reduces the negative externalities of management compared to EM. We propose that future research in drained peatland forests should focus on assessing the economic and environmental feasibility of CCF.

Published
2018

42. Biomarkers as predictors of sudden cardiac death in coronary artery disease patients with preserved left ventricular function (ARTEMIS study)

Author

Lepojärvi, E. S. (E. Samuli), Huikuri, H. V. (Heikki V.), Piira, O.-P. (Olli-Pekka), Kiviniemi, A. M. (Antti M.), Miettinen, J. A. (Johanna A.), Kenttä, T. (Tuomas), Ukkola, O. (Olavi), Perkiömäki, J. S. (Juha S.), Tulppo, M. P. (Mikko P.), and Junttila, M. J. (M. Juhani)

Abstract

Aims: Biomarkers have shown promising results in risk assessment of cardiovascular events. Their role in predicting the risk of sudden cardiac death (SCD) is not well established. We tested the performance of several biomarkers in risk assessment for SCD in patients with coronary artery disease (CAD) and preserved left ventricular function. Methods and results: The study population consisted of 1,946 CAD patients (68% male; mean age 66.9±8.6 yrs; type 2 diabetes (T2D) 43%) enrolled in the ARTEMIS study. The study subjects underwent examinations with echocardiography and measurement of several biomarkers. The primary endpoint of the study was SCD. During the mean follow up of 76±20 months 50 patients experienced SCD. Elevated high sensitive CRP (hs-CRP, p = 0.001), soluble ST2 (sST2, p

Published
2018

47. Global Demand for Natural Resources EliminatedMore Than 100,000 Bornean Orangutans

Author

Voigt, M, Wich, SA, Ancrenaz, M, Meijaard, E, Abram, N, Banes, GL, Campbell-Smith, G, d'Arcy, LJ, Delgado, RA, Erman, A, Gaveau, D, Goossens, B, Heinicke, S, Houghton, M, Husson, SJ, Leiman, A, Sanchez, KL, Makinuddin, N, Marshall, AJ, Meididit, A, Miettinen, J, Mundry, R, Musnanda, Nardiyono, Nurcahyo, A, Odom, K, Panda, A, Prasetyo, D, Priadjati, A, Purnomo, Rafiastanto, A, Russon, AE, Santika, T, Sihite, J, Spehar, S, Struebig, M, Sulbaran-Romero, E, Tjiu, A, Wells, J, Wilson, KA, Kuehl, HS, Voigt, M, Wich, SA, Ancrenaz, M, Meijaard, E, Abram, N, Banes, GL, Campbell-Smith, G, d'Arcy, LJ, Delgado, RA, Erman, A, Gaveau, D, Goossens, B, Heinicke, S, Houghton, M, Husson, SJ, Leiman, A, Sanchez, KL, Makinuddin, N, Marshall, AJ, Meididit, A, Miettinen, J, Mundry, R, Musnanda, Nardiyono, Nurcahyo, A, Odom, K, Panda, A, Prasetyo, D, Priadjati, A, Purnomo, Rafiastanto, A, Russon, AE, Santika, T, Sihite, J, Spehar, S, Struebig, M, Sulbaran-Romero, E, Tjiu, A, Wells, J, Wilson, KA, and Kuehl, HS

Abstract

Unsustainable exploitation of natural resources is increasingly affecting the highly biodiverse tropics [1, 2]. Although rapid developments in remote sensing technology have permitted more precise estimates of land-cover change over large spatial scales [3-5], our knowledge about the effects of these changes on wildlife is much more sparse [6, 7]. Here we use field survey data, predictive density distribution modeling, and remote sensing to investigate the impact of resource use and land-use changes on the density distribution of Bornean orangutans (Pongo pygmaeus). Our models indicate that between 1999 and 2015, half of the orangutan population was affected by logging, deforestation, or industrialized plantations. Although land clearance caused the most dramatic rates of decline, it accounted for only a small proportion of the total loss. A much larger number of orangutans were lost in selectively logged and primary forests, where rates of decline were less precipitous, but where far more orangutans are found. This suggests that further drivers, independent of land-use change, contribute to orangutan loss. This finding is consistent with studies reporting hunting as a major cause in orangutan decline [8-10]. Our predictions of orangutan abundance loss across Borneo suggest that the population decreased by more than 100,000 individuals, corroborating recent estimates of decline [11]. Practical solutions to prevent future orangutan decline can only be realized by addressing its complex causes in a holistic manner across political and societal sectors, such as in land-use planning, resource exploitation, infrastructure development, and education, and by increasing long-term sustainability [12]. VIDEO ABSTRACT.

Published
2018

50. Miten puhe on taidetta?

Author

Miettinen, J. (Jari)

Subjects
Education
Abstract

Tutkielman tavoitteena oli tutkia, miten puhe on taidetta. Tutkimus tarjosi metodiksi puhetaiteelle puheen ilmaisumuotoja, jotka olivat tutkimuksen keskeinen ongelma. Tutkielma kuvasi ja kartoitti puheenmuodostuksesta peräisin olevia ilmaisumuotoja. Puheenmuodostus on kehitetty 1910-luvulla Rudolf Steinerin antroposofian pohjalta. Puheenmuodostusta ei ole ymmärrettävä kieleksi, johon liittyy pelkkä subjektin tarve puhua, vaan eläväksi käytännöksi, joka olemassaolollaan välittömästi liittää yleisön esitykseen. Tutkielman kirjoittaja on 30 vuotta työskennellyt ilmaisumuodoista tietoisena. Tutkielma kartoitti laadullisesti puheen ilmaisumuotojen valintaa diskurssianalyysillä ja niiden käyttöä esityksessä. Lisäksi tutkielma kuvasi akustisen fonetiikan analyysilla perustaajuuden- ja ajoituksenpiirteitä puheen ilmaisumuotojen esiintymisessä. Tutkielmaa voi luonnehtia monimenetelmälliseksi eli triangulaatio tutkimukseksi, jossa kvalitatiivista tutkimusta täydentää kvantitatiivinen osuus, vahvistaen ilmaisumuotojen näkyvyyttä ja lisäten tutkimuksen luotettavuutta. Tutkielma jakautuu teoriaosuuteen kirjallisuuskatsauksineen, laadulliseen osuuteen, jossa analysointi toteutettiin heuristisella reflektoivalla analyysilla ja määrälliseen fonetiikan osuuteen. Tutkimuksen molemmissa empiirisissä osioissa käytettiin primääriaineistoa, jonka tutkija itse loi. Kvalitatiivisen osion aineistona oli tutkijan laatima työpäiväkirja ja kvantitatiivisen tutkimuksen aineiston tutkija loi nauhoittaen ilmaisumuotoista puhettaan. Tutkielma vahvisti tekijän kokemuksellisen etukäteisodotuksen puheen ilmaisumuotojen ominaisuuksista. Kuudesta ilmaisumuodosta ’osoittava’, ’kysyvä’ ja ’erottava’ suuntautuvat ulospäin, ulkoisiin havaintoihin ja ’miettivä’, ’liittävä’ ja ’todistava’ sisäänpäin, sisäisyyden havaintoihin. Tulokset olivat luettavissa erityisesti perustaajuuden ja sen muutosnopeuden muutoksista. Tutkielmassa kehitettiin ilmaisumuotojen valintametodi diskurssianalyyttista ajattelua hyödyntäen. Tutkielman teoriaosuus selvensi Steinerin näyttämötaiteen impulssin luonnetta kommentoiden David Mametin kirjoituksilla. Tutkielma vastasi puheen olevan taidetta ilmaisumuotojen avulla. Fonetiikka näyttäytyi puhetaiteen tutkimusalustaksi. Tutkielma oli tapaustutkimus ja sen luotettavuus näyttäytyy yksittäisen puhetaiteilijan kontekstissa. Tutkielmaan liittyy pedagoginen aspekti. Taiteellinen pedagogiikka voi yksinkertaisimmillaan toimia jo ihmisen puheessa. Tutkielma selvensi puheen olevan pedagoginen alue tuoda kasvatukseen ihmisen kokonaisuuden kokemus. Tutkielma opettaa ihmisiä löytämään tekstistä puheen ilmaisumuotoja ja käyttämään niitä. Ilmaisumuotojen avulla lasten parissa toimivat aikuiset voivat esimerkiksi rohkaistua tavoittelemaan vivahteikasta puheilmaisua. Kun puhe on puhetaiteen laadullisuuksilla työstettyä, voi laadut heijastua lapsen arkeen iässä, jolloin ympäristön vaikutukset jättävät lapsiin pitkälle tulevaisuuteen vaikuttavia jälkiä. Jatkotutkimuksia aiheesta voi odottaa niin teatterin, fonetiikan kuin pedagogiikan alalta.

Published
2017

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