@article {Simula.simula.1594,
	title = {Improved Discretisation and Linearisation of Active Tension in Strongly Coupled Cardiac Electro-Mechanics Simulations},
	journal = {Computer Methods in Biomechanics and Biomedical Engineering},
	volume = {17},
	number = {6},
	year = {2014},
	pages = {604-15},
	publisher = { },
	abstract = {Mathematical models of cardiac electro-mechanics typically consist of three tightly coupled parts: systems of ordinary differential equations describing electro-chemical reactions and cross-bridge dynamics in the muscle cells, a system of partial differential equations modelling the propagation of the electrical activation through the tissue and a nonlinear elasticity problem describing the mechanical deformations of the heart muscle. The complexity of the mathematical model motivates numerical methods based on operator splitting, but simple explicit splitting schemes have been shown to give severe stability problems for realistic models of cardiac electro-mechanical coupling. The stability may be improved by adopting semi-implicit schemes, but these give rise to challenges in updating and linearising the active tension. In this paper we present an operator splitting framework for strongly coupled electro-mechanical simulations and discuss alternative strategies for updating and linearising the active stress component. Numerical experiments demonstrate considerable performance increases from an update method based on a generalised Rush-Larsen scheme and a consistent linearisation of active stress based on the first elasticity tensor.},
	author = {Sundnes, Joakim and Wall, Samuel and Osnes, Harald and Thorvaldsen, Tom and Andrew D. {McCulloch}}
}
@article {Simula.simula.188,
	title = {A Parallel Block Preconditioner for Large Scale Poroelasticity With Highly Heterogeneous Material Parameters},
	journal = {Computational Geosciences},
	volume = {16},
	number = {3},
	year = {2012},
	month = {June},
	pages = {723-734},
	abstract = {Large-scale simulations of coupled flow in deformable porous media require iterative methods for solving the systems of linear algebraic equations. Construction of efficient iterative methods is particularly challenging in problems with large jumps in material properties, which is often the case in realistic geological applications, such as basin evolution at regional scales. The success of iterative methods for such problems depends strongly on finding effective preconditioners with good parallel scaling properties, which is the topic of the present paper. We present a parallel preconditioner for Biot{\textquoteright}s equations of coupled elasticity and fluid flow in porous media. The preconditioner is based on an approximation of the exact inverse of the two-by-two block system arising from a finite element discretisation. The approximation relies on a highly scalable approximation of the global Schur complement of the coefficient matrix, combined with generally available state-of-the-art multilevel preconditioners for the individual blocks. This preconditioner is shown to be robust on problems with highly heterogeneous material parameters. We investigate the weak and strong parallel scaling of this preconditioner on up to 512 processors, and demonstrate its ability on a realistic basin-scale problem in poroelasticity with over 8 million tetrahedral elements.},
	doi = {10.1007/s10596-012-9284-4},
	author = {Joachim Berdal {Haga} and Hans Petter {Langtangen} and Osnes, Harald}
}
@article {heartmech-uncertainty,
	title = {Uncertainty Analysis of Ventricular Mechanics Using the Probabilistic Collocation Method},
	journal = {IEEE Transactions on Biomedical Engineering},
	volume = {59},
	number = {8},
	year = {2012},
	month = {August},
	pages = {2171-2179},
	abstract = {Uncertainty and variability in material parameters are fundamental challenges in computational biomechanics. Analyzing and quantifying the resulting uncertainty in computed results with parameter sweeps or Monte Carlo methods has become very computationally demanding. In this paper we consider a stochastic method named the probabilistic collocation method, and investigate its applicability for uncertainty analysis in computing the passive mechanical behaviour of the left ventricle. Specifically, we study the effect of uncertainties in material input parameters upon response properties such as the increase in cavity volume, the elongation of the ventricle, the increase in inner radius, the decrease in wall thickness and the rotation at apex. The numerical simulations conducted herein indicate that the method is well suited for the problem of consideration, and is far more efficient than the Monte Carlo simulation method for obtaining a detailed uncertainty quantification. The numerical experiments also give interesting indications on which material parameters are most critical for accurately determining various global responses.},
	author = {Osnes, Harald and Sundnes, Joakim}
}
@article {Simula.simula.18,
	title = {On the Causes of Pressure Oscillations in Low-Permeable and Low-Compressible Porous Media},
	journal = {International Journal for Numerical and Analytical Methods in Geomechanics},
	number = {online},
	year = {2011},
	month = {July},
	abstract = {Non-physical pressure oscillations are observed in finite element calculations of Biot{\textquoteright}s poroelastic equations in low-permeable media. These pressure oscillations may be understood as a failure of compatibility between the finite element spaces, rather than elastic locking. We present evidence to support this view by comparing and contrasting the pressure oscillations in low-permeable porous media with those in low-compressible porous media. As a consequence, it is possible to use established families of stable mixed elements as candidates for choosing finite element spaces for Biot{{\textquoteright}}s equations.},
	doi = {10.1002/nag.1062},
	author = {Joachim Berdal {Haga} and Osnes, Harald and Hans Petter {Langtangen}}
}
@article {Simula.SC.660,
	title = {Efficient Block Preconditioners for the Coupled Equations of Pressure and Deformation in Highly Discontinuous Media},
	journal = {International Journal for Numerical and Analytical Methods in Geomechanics},
	volume = {35},
	number = {13},
	year = {2011},
	month = {November},
	pages = {1466-1482},
	abstract = {Large-scale simulations of flow in deformable porous media require efficient iterative methods for solving the involved systems of linear algebraic equations. Construction of efficient iterative methods is particularly challenging in problems with large jumps in material properties, which is often the case in geological applications, such as basin evolution at regional scales. The success of iterative methods for this type of problems depends strongly on finding effective preconditioners. This paper investigates how the block-structured matrix system arising from single-phase flow in elastic porous media should be preconditioned, in particular for highly discontinuous permeability and significant jumps in elastic properties. The most promising preconditioner combines algebraic multigrid with a Schur complement-based exact block decomposition. The paper compares numerous block preconditioners with the aim of providing guidelines on how to formulate efficient preconditioners.},
	doi = {10.1002/nag.973},
	author = {Joachim Berdal {Haga} and Osnes, Harald and Hans Petter {Langtangen}}
}
@misc {Simula.sc.712,
	title = {Computer Modeling of Cardiac Electro-Mechanics - Models and Numerical Methods},
	howpublished = {Talk at Cardiac Modeling seminar, Simula Research Laboratory},
	year = {2009},
	month = {February},
	author = {Sundnes, Joakim and Wall, Samuel and Osnes, Harald}
}
@article {Simula.SC.628,
	title = {Experimental and Analytical Strength Analysis of Double-Lap Joints for Marine Applications},
	journal = {Composites Part B: Engineering},
	volume = {40},
	number = {1},
	year = {2009},
	pages = {29-40},
	abstract = {Weight-critical marine structures, such as high-speed craft, are often made of high-strength aluminium, and the usual joining method is welding. To improve the performance of high-speed craft there is a tendency to seeking lighter weight materials, especially in parts of the structure where weight-saving is particularly beneficial, such as in the superstructure. Light-weight materials can be fibre-reinforced composites. When joining structures made of composites to components of aluminium or steel, welding is no longer an option. On the other hand, adhesive bonding becomes an attractive joining method. Thus, there is a need to investigate the strength of bonded steel-composite joints. In the present paper, the stress distribution and strength of bonded double-lap steel-composite joints are investigated through theoretical analysis and experimental testing. The strength of a set of joints, with a variety of overlap lengths and two different bonding techniques and environmental conditions, has been measured experimentally. Furthermore, a new elastic-plastic stress analysis, accounting for adhesive shear deformations as well as axial and shear deformations in the adherends, has been derived. Predictions using the new theory derived herein as well as linear models are compared with the reported results. It is clearly demonstrated that linear theories are completely inappropriate for modelling such joints when loaded to failure. On the other hand, the strength predictions obtained by the new nonlinear theory agree well with the experimental results.},
	author = {Osnes, Harald and McGeorge, Dag}
}
@inproceedings {Simula.SC.504,
	title = {Numerical Simulation of Low-Velocity Impact Loading of Polymeric Materials},
	journal = {The 7th European LS-DYNA Conference},
	year = {2009},
	month = {May},
	publisher = {LS Dyna},
	type = {Conference},
	isbn = {0-9753707-5-8},
	author = {Daiyan, Hamid and Grytten, Frode and Andreassen, Erik and Ole Vidar {Lyngstad} and Osnes, Harald and Gaarder, Rune and Hinrichsen, Einar}
}
@misc {Simula.sc.1146,
	title = {On the Perfermance of an Algebraic Multigrid Preconditioner for the Pressure Equationwith Highly Discontinuous Media},
	howpublished = {Talk at MekIT{\textquoteright}09: Fifth National Conference on Computational Mechanics, Trondheim, May 26-27},
	year = {2009},
	author = {Joachim Berdal {Haga} and Hans Petter {Langtangen} and Nielsen, Bj{\o}rn Fredrik and Osnes, Harald}
}
@inproceedings {Simula.SC.568,
	title = {On the Performance of an Algebraic Multigrid Preconditioner for the Pressure Equation With Highly Discontinuous Media},
	journal = {MekIT{\textquoteright}09.~~Fifth~~national~~conference~~on~~Computational~~Mechanics},
	year = {2009},
	month = {May},
	pages = {191-204},
	publisher = {NTNU},
	type = {Conference},
	abstract = {We study the performance of an algebraic multigrid (AMG) preconditioner combined with conjugate gradient-type methods for the pressure equation in the presence of strong discontinuity of the permeability. Such discontinuities are problematic for iterative solvers, due to the dependence of the condition number of the discretized linear system of equations on the magnitude of the discontinuities. We identify two separate causes of such ill-conditioning, and assess how well the AMG preconditioner handles these. For the more difficult problems, we discuss techniques to modify the model to allow iterative solutions.},
	isbn = {978-82-519-2421-4},
	author = {Joachim Berdal {Haga} and Hans Petter {Langtangen} and Nielsen, Bj{\o}rn Fredrik and Osnes, Harald},
	editor = {Bj{\o}rn H. {Skallerud} and H. I. {Andersson}}
}
@misc {Simula.sc.716,
	title = {Simulation of Strongly Coupled Electro-Mechanics in an Infarcted Left Ventricle},
	howpublished = {Invited talk at the workshop Bidomain 2009, University of Graz},
	year = {2009},
	author = {Sundnes, Joakim and Wall, Samuel and Osnes, Harald}
}
@inproceedings {Simula.sc.820,
	title = {Uncertainty Analysis of the Mechanics of the Heart},
	journal = {Proceedings of the Twenty Second Nordic Seminar on Computational Mechanics},
	number = {11},
	year = {2009},
	publisher = {Aalborg University. Department of Civil Engineering},
	type = {1},
	chapter = {245-248},
	isbn = {1901-7278},
	author = {Osnes, Harald and Clark, Stuart and Sundnes, Joakim},
	editor = {Damkilde, L. and Andersen, L. and Kristensen, A.S. and Lund, E.}
}
@inproceedings {Simula.SC.502,
	title = {Experimental and Analytical Analysis of Bonded Joint for Marine Applications},
	journal = {Proceedings of the II International Conference on Computational Methods in Marine Engineering - MARINE 2007},
	year = {2007},
	month = {June},
	publisher = {International Center of Numerical Methods in Engineering (CIMNE)},
	type = {Conference},
	abstract = {Weight-critical marine structures, such as high-speed craft, are often made of high-strength aluminium. To improve the performance of such structures, there is a tendency to seeking lighter weight materials, especially in parts of the structure where weight-saving is particularly beneficial, such as in the superstructure. Such leight-weight materials can be fibre-reinforced composites. When joining structures made of composites to components of steel or aluminium, welding, which is the traditional joining method in marine applications, is no longer an option. Instead, adhesive bonding becomes an attractive joining method. In the present work the strength of different bonded double-lap steel-composite joints, with a variety of overlap lengths and environmental conditions, has been measured experimentally. These experimental results have been compared with predictions using an elastic-plastic theory recently derived by the present authors, as well as linear models. It is demonstrated that predictions using the new nonlinear theory agree well with the experimentally obtained results, while linear analysis is inappropriate for modeling such joints when loaded to failure.},
	isbn = {978-84-96736-19-1},
	author = {Osnes, Harald and McGeorge, Dag},
	editor = {O{\~n}ate, E. and Pedro J. {Garcia} and Bergan, P. and Kvamsdal, T.}
}
@techreport {Simula.SC.72,
	title = {Mohr-Coulomb Stress in the Code for Deformation and Heat Flow in Sedimentary Basins},
	year = {2007},
	publisher = {Simula Research Laboratory},
	author = {Osnes, Harald}
}
@inproceedings {Simula.SC.18,
	title = {Parallelisation and Numerical Performance of a 3D Model for Coupled Deformation, Fluid Flow and Heat Transfer in Sedimentary Basins},
	journal = {MekIT{\textquoteright}07. Fourth National Conference on Computational Mechanics},
	year = {2007},
	month = {May},
	pages = {151-162},
	publisher = {Tapir Academic Press},
	type = {Conference},
	address = {Trondheim},
	abstract = {In this paper, we present some parallel performance results for a 3D simulator of coupled deformation, fluid flow and heat transfer in sedimentary basins. The model parameters are derived from an industry simulator, with realistic material properties and complex irregular grids of up to 1.5 million nodes with 7.3 million degrees of freedom. We have performed parallelisation on the linear algebra level using the ML algebraic multigrid preconditioner with iterative methods in the Diffpack finite element framework. Implementation and speedup results are presented.},
	isbn = {978-82-519-2235-7},
	author = {Joachim Berdal {Haga} and Are Magnus {Bruaset} and Cai, Xing and Hans Petter {Langtangen} and Osnes, Harald and Skogseid, Jakob},
	editor = {Bj{\o}rn H. {Skallerud} and H. I. {Andersson}}
}
@misc {Simula.SC.101,
	title = {Parallelisation and Numerical Performance of a 3D Model for Coupled Deformation, Fluid Flow, and Heat Transport in Porous Geological Formations},
	howpublished = {Talk at the Fourth National Conference on Computational Mechanics (MekIT{\textquoteright}07), Trondheim, Norway},
	year = {2007},
	note = {Presented by J. B. Haga},
	month = {may},
	abstract = {In this paper, we present some parallel performance results for a 3D simulator of coupled deformation, fluid flow and heat transfer in sedimentary basins. The model parameters are derived from an industry simulator, with realistic material properties and complex irregular grids of up to 1.5 million nodes with 7.3 million degrees of freedom. We have performed parallelisation on the linear algebra level using the ML algebraic multigrid preconditioner with iterative methods in the Diffpack finite element framework. Implementation and speedup results are presented.},
	author = {Joachim Berdal {Haga} and Are Magnus {Bruaset} and Cai, Xing and Hans Petter {Langtangen} and Osnes, Harald and Skogseid, Jakob}
}
@techreport {Simula.SC.490,
	title = {PhD: Simulation of Deformation and Heat Flow in Sedimentary Basins},
	year = {2007},
	note = {StatoilHydro collaboration (contract \#5377415)},
	month = {December},
	publisher = {Simula},
	author = {Joachim Berdal {Haga} and Osnes, Harald and Hans Petter {Langtangen} and Are Magnus {Bruaset}}
}
@misc {Thorvaldsen.2005.3,
	title = {A Mixed FEM for Modeling the Passive Mechanical Properties of the Myocardium},
	howpublished = {Talk at the SIAM Conference on Computational Science \& Engineering},
	year = {2005},
	month = {February},
	author = {Thorvaldsen, Tom and Osnes, Harald and Sundnes, Joakim}
}
@article {Thorvaldsen.2005.1,
	title = {A Mixed Finite Element Formulation for a Nonlinear, Transversely Isotropic Material Model for the Cardiac Tissue},
	journal = {Computer Methods in Biomechanics and Biomedical Engineering},
	volume = {8},
	number = {6},
	year = {2005},
	month = {December},
	pages = {369-379},
	abstract = {In this paper we present a mixed finite element method for modeling the passive properties of the myocardium. The passive properties are described by a non-linear, transversely isotropic, hyperelastic material model, and the myocardium is assumed to be almost incompressible. Single-field, pure displacement-based formulations are known to cause numerical difficulties when applied to incompressible or slightly compressible material cases. This paper presents an alternative approach in the form of a mixed formulation, where a separately interpolated pressure field is introduced as a primary unknown in addition to the displacement field. Moreover, a constraint term is included in the formulation to enforce (almost) incompressibility. Numerical results presented in the paper demonstrate the difficulties related to employing a pure displacement-based method, applying a set of physically relevant material parameter values for the cardiac tissue. The same problems are not experienced for the proposed mixed method. We show that the mixed formulation provides reasonable numerical results for compressible as well as nearly incompressible cases, also in situations of large fiber stretches. There is good agreement between the numerical results and the underlying analytical models.},
	author = {Thorvaldsen, Tom and Osnes, Harald and Sundnes, Joakim}
}
@inproceedings {Thorvaldsen.2005.2,
	title = {A Mixed Formulation for Modeling the Mechanical Bahavior of the Heart},
	journal = {MekIt05 - Third national conference om Computational Mechanics, Trondheim May 11-12},
	year = {2005},
	month = {May},
	pages = {327-341},
	publisher = {Tapir Academic Press},
	type = {1},
	abstract = {In this paper we present a mixed finite element formulation for modeling the mechanical behavior of the cardiac tissue. The modeling may be divided into a passive and an active part. The passive properties are in this work described by a transversely isotropic, hyperelastic material model. Moreover, the myocardium is assumed to be almost incompressible. In advanced models the active contraction is strongly connected to electro-physiological processes in the muscle cells. In this paper we simplify the active stress contribution by modeling it as a linear function in time. Due to the fact that the heart muscle undergoes large deformations during contraction, both material and geometrical non-linearities must be taken into account in the analysis. Numerical results are presented for different activation patterns applied to a box-shaped test specimen, which represents a piece of the myocardial wall. The proposed mixed method offers reasonable results in the modeling of the mechanical behavior of the test specimen.},
	author = {Thorvaldsen, Tom and Sundnes, Joakim and Osnes, Harald},
	editor = {Bj{\o}rn H. {Skallerud} and Helge I. {Andersson}}
}
@techreport {Thorvaldsen.2005.4,
	title = {Non-Linear Elasticity With Applications to Heart Mechanics},
	number = {2005-16},
	year = {2005},
	publisher = {Simula Research Laboratory},
	abstract = {This report gives an introduction to mathematical and numerical modeling of large-deformation elasticity problems. Basic non-linear continuum mechanics is presented along with a set of hyperelastic material models. Two alternative finite element formulations are described for solving such problems, for compressible and almost incompressible materials. Simulation results are presented for both methods. The elasticity solver is employed in simulating the mechanical behavior of the heart. Mathematical models are presented for describing the passive behavior of cardiac tissue and the active force development. Moreover, we show mathematical models and numerical algorithms for simulating the large deformations of the left ventricle during a heart beat.},
	author = {Thorvaldsen, Tom and Sundnes, Joakim and Osnes, Harald}
}
@misc {SC.7.Osnes.2004,
	title = {BONDSHIP Guidelines},
	howpublished = {Recommended Practice, Det Norske Veritas},
	year = {2004},
	author = {Osnes, Harald}
}
@techreport {SC.7.Thorvaldsen.2004,
	title = {Numerical Modeling of Isotropic, Hyperelastic Materials Undergoing Large Deformations},
	number = {2004-06},
	year = {2004},
	publisher = {Simula Research Laboratory},
	author = {Thorvaldsen, Tom and Sundnes, Joakim and Osnes, Harald}
}
@misc {SC.4.osnes.2003.b,
	title = {Analysis of Overlaminated Double-Lap Joints},
	howpublished = {Misc},
	year = {2003},
	note = {Submitted to Composites: Part B},
	author = {Osnes, Harald and McGeorge, D.}
}
@misc {SC.7.Osnes.2003.a,
	title = {Composite Components},
	howpublished = {Offshore Standard, DNV-OS-C501, Det Norske Veritas},
	year = {2003},
	author = {Osnes, Harald}
}
@misc {SC.7.Osnes.2003.b,
	title = {Composite Risers},
	howpublished = {Recommended Practice, DNV-RP-F202, Det Norske Veritas},
	year = {2003},
	author = {Osnes, Harald}
}
@article {SC.4.osnes.2003.a,
	title = {Computational Analysis of Geometric Nonlinear Effects in Adhesively Bonded Single Lap Composite Joints},
	journal = {Composites Part B: Engineering},
	volume = {34},
	year = {2003},
	pages = {417-427,},
	author = {Osnes, Harald and Andersen, A.}
}
@inbook {SC.5.Thorvaldsen.2003.a,
	title = {Finite Element Modeling of Elastic Structures},
	booktitle = {Advanced Topics in Computational Partial Differential Equations - Numerical Methods and Diffpack Programming},
	series = {Lecture Notes in Computational Science and Engineering},
	year = {2003},
	pages = {507-576},
	publisher = {Springer},
	organization = {Springer},
	author = {Thorvaldsen, Tom and Hans Petter {Langtangen} and Osnes, Harald},
	editor = {Hans Petter {Langtangen} and Tveito, Aslak}
}
@inproceedings {SC.5.hayman.2003,
	title = {Non-Linear Response of Laterally Loaded FRP Sandwich Panels for High Speed Craft},
	journal = {Proceedings of the Fast Sea Transportation (FAST{\textquoteright}03)},
	year = {2003},
	month = {October,},
	type = {1},
	address = {Ischia, Italy},
	author = {Hayman, B. and Osnes, Harald and McGeorge, D.}
}
@inproceedings {SC.5.Langtangen.2003,
	title = {Stochastic Partial Differential Equations},
	journal = {Advanced Topics in Computational Partial Differential Equations - Numerical Methods and Diffpack Programming},
	year = {2003},
	pages = {257-320},
	publisher = {Springer-Verlag},
	type = {1},
	author = {Hans Petter {Langtangen} and Osnes, Harald},
	editor = {Hans Petter {Langtangen} and Tveito, Aslak}
}
@inproceedings {SC.5.hayman.2002,
	title = {Exploiting the Non-Linear Response of Sandwich Panels in High Speed Craft Design},
	journal = {Proceedings of the High Performance Marine Vehicles (HIPER{\textquoteright}02)},
	year = {2002},
	month = {September 15-17,},
	type = {1},
	address = {Bergen, Norway},
	author = {Hayman, B. and Osnes, Harald and Skiple, A. and McGeorge, D.}
}
@inproceedings {SC.5.echtermeyer.2002,
	title = {Recommended Practice for Composite Risers},
	journal = {Proceedings of the Offshore Technology Conference},
	year = {2002},
	month = {May 6-9,},
	type = {1},
	address = {Houston, Texas, USA},
	author = {A. T. {Echtermeyer} and Osnes, Harald and K. O. {Ronold} and E. T. {Moe}}
}
@techreport {SC.7.Osnes.2001,
	title = {Implementation of a Geometrically Nonlinear Module for CompositeMaterials in Diffpack},
	year = {2001},
	publisher = {University of Oslo},
	author = {Osnes, Harald}
}
@inproceedings {SC.5.andersen.2000,
	title = {Computational Analysis of Composite Joints},
	journal = {Proceedings of the 13th Nordic Seminar on Computational Mechanics},
	year = {2000},
	month = {October 20-21,},
	type = {1},
	address = {Oslo, Norway},
	author = {Andersen, A. and Osnes, Harald and Hellesland, J.}
}
@techreport {SC.7.andersen.2000,
	title = {Computational Analysis of Geometric Nonlinear Effects in Adhesively Bonded Single Lap Composite Joints},
	year = {2000},
	publisher = {University of Oslo},
	author = {Andersen, A. and Osnes, Harald}
}
@inproceedings {SC.5.andersen.1999,
	title = {Computational Analysis of Geometric Nonlinear Effects in Adhesively Bonded Single Lap Composite Joints},
	journal = {Proceedings of the 12th Nordic Seminar on Computational Mechanics},
	year = {1999},
	month = {October 22-23,},
	type = {1},
	address = {Helsinki, Finland},
	author = {Andersen, A. and Osnes, Harald}
}
@techreport {SC.7.Berge.1999.b,
	title = {Coupling of PDEs in Diffpack Environments},
	year = {1999},
	publisher = {SINTEF},
	author = {Berge, J. and Are Magnus {Bruaset} and Erlandsen, H. and Holm, E. and Ingebrigtsen, L. and Hans Petter {Langtangen} and Osnes, Harald and Rusten, T.}
}
@misc {SC.8.osnes.1999,
	title = {Quantifying the Relative Contributions From Individual Alpha-1-Adrenoceptor Subtypes by the Monte Carlo Simulation Method},
	howpublished = {Presentation at Vinterm{\o}tet for Norsk selskap for farmakologi og toksikologi, Beito, Norway, January 28-30},
	year = {1999},
	author = {Osnes, Harald and G. {\O} {Andersen} and J. -B {Osnes}}
}
@article {SC.4.Osnes.1998.f,
	title = {An Improved Probabilistic Finite Element Method for Stochastic Groundwater Flow},
	journal = {Advances in Water Resources},
	volume = {22},
	year = {1998},
	pages = {185-195,},
	author = {Osnes, Harald and Hans Petter {Langtangen}}
}
@misc {SC.8.osnes.1998,
	title = {Quantifying the Relative Contribution From Individual Alpha-1-Adrenoceptors by the Monte Carlo Simulation Method},
	howpublished = {Presentation at the Troms{\o} Seminar in Medicine, Troms{\o} , Norway, August 30th - September 1st},
	year = {1998},
	author = {J. -B {Osnes} and Osnes, Harald and G. {\O}. {Andersen}}
}
@article {SC.4.osnes.1998.d,
	title = {Quantifying the Relative Contributions From Individual Alpha-1-Adrenoceptor Subtypes by the Monte Carlo Simulation Method},
	journal = {Hjerteforum},
	volume = {11},
	number = {1},
	year = {1998},
	pages = {119-129,},
	author = {Osnes, Harald and G. {\O} {Andersen} and J. -B {Osnes}}
}
@article {SC.4.osnes.1998.b,
	title = {Stochastic Analysis of Velocity Spatial Variability in Bounded Rectangular Aquifers},
	journal = {Advances in Water Resources},
	volume = {21},
	number = {3},
	year = {1998},
	pages = {203-215,},
	author = {Osnes, Harald}
}
@misc {SC.7.Langtangen.1998,
	title = {Stochastic Methods in Diffpack},
	howpublished = {Oslo Scientific Computing Archive},
	year = {1998},
	author = {Hans Petter {Langtangen} and Osnes, Harald}
}
@article {SC.4.osnes.1998.e,
	title = {A Study of Some Finite Difference Schemes for a Uni-Directional Stochastic Transport Equation},
	journal = {SIAM Journal on Scientific Computing},
	volume = {19},
	number = {3},
	year = {1998},
	pages = {799-812,},
	author = {Osnes, Harald and Hans Petter {Langtangen}}
}
@article {SC.4.Osnes.1998.a,
	title = {A Study of Some Finite Difference Schemes for a Uni-Directional Stochastic Treansport Equation},
	journal = {SIAM Journal on Scientific Computing},
	volume = {19},
	number = {3,},
	year = {1998},
	author = {Osnes, Harald and Hans Petter {Langtangen}}
}
@techreport {SC.7.Langtangen.1997.c,
	title = {A Clustered Weighted Integral Method for Stochastic Porous Media Flow},
	year = {1997},
	publisher = {SINTEF},
	author = {Hans Petter {Langtangen} and Osnes, Harald}
}
@misc {SC.8.Berge.1997,
	title = {An Environment for Reservoir Simulation},
	howpublished = {Talk at the Fourth SIAM Conference on Computational and Mathematical Issues in the Geosciences, Albuquerque, New Mexico, USA},
	year = {1997},
	note = {Presented by H. Erlandsen},
	month = {June},
	author = {Berge, J. and Erlandsen, H. and Ingebrigtsen, L. and Hans Petter {Langtangen} and Osnes, Harald}
}
@techreport {SC.7.Langtangen.1997.b,
	title = {An Object-Oriented Design of a Simulator for Stochastic Groundwater Flow},
	year = {1997},
	publisher = {SINTEF},
	author = {Hans Petter {Langtangen} and Osnes, Harald}
}
@misc {SC.8.osnes.1997,
	title = {Stochastic Analysis of Groundwater Flow},
	howpublished = {Presentation at the Nordic Computational Differential Equations Circus, Oslo, Norway, January 7-8},
	year = {1997},
	author = {Osnes, Harald}
}
@techreport {SC.7.Langtangen.1997.a,
	title = {Stochastic Methods in Diffpack},
	year = {1997},
	publisher = {SINTEF},
	author = {Hans Petter {Langtangen} and Osnes, Harald}
}
@techreport {SC.7.osnes.1997,
	title = {Variance Reduction Techniques for Monte Carlo Simulation},
	year = {1997},
	publisher = {SINTEF},
	author = {Osnes, Harald}
}
@phdthesis {SC.3.osnes.1996,
	title = {Stochastic Analysis of Groundwater Flow},
	year = {1996},
	school = {University of Oslo},
	type = {phd},
	author = {Osnes, Harald}
}
@article {SC.4.osnes.1995,
	title = {Stochastic Analysis of Head Spatial Variability in Bounded Rectangular Aquifers},
	journal = {Water Resources Research},
	volume = {31},
	number = {12},
	year = {1995},
	pages = {2981-2990},
	author = {Osnes, Harald}
}
@mastersthesis {SC.7.Osnes.1991,
	title = {Solution of the Euler Equations by the Finite Element Method},
	year = {1991},
	publisher = {University of Oslo},
	type = {masters},
	author = {Osnes, Harald}
}
