Browsing by Author "Moxnes, John Fredrik"
Now showing items 1-20 of 28
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All Molecular Surfaces are Equal: Demanding Invariance of Predictions in Linear Single-Variable Models
Kjønstad, Eirik; Moxnes, John Fredrik; Jensen, Tomas Lunde; Unneberg, Erik (2016)The molecular surface has been suggested to be a region of the molecule where information of non-covalent intermolecular interactions is present. Many workers have pursued this idea by constructing models based on statistical ... -
Calculation of decomposition products from components of gunpowder by using ReaxFF reactive force field molecular dynamics and thermodynamic calculations of equilibrium composition
Jensen, Tomas Lunde; Moxnes, John Fredrik; Unneberg, Erik; Dullum, Ove (2014)The major combustion products from munitions containing nitro-based propellants are water, carbon monoxide, carbon dioxide, hydrogen and nitrogen. In addition, compounds including hydrogen cyanide, ammonia, methane, nitrogen ... -
Comparing VO2max Improvement in Five Training Methods
Moxnes, John Fredrik; Hausken, Kjell (2012)This paper presents a theoretical study comparing the improvement of the whole body maximum oxygen uptake (maximum aerobic power or VO2max) when training at different intensities and with different methods matched for ... -
A computational study of density of some high energy molecules
Moxnes, John Fredrik; Hansen, Finn Knut; Jensen, Tomas Lunde; Sele, Marta Lill; Unneberg, Erik (2016)The detonation pressure depends quadratically on the loading density of the explosives. A precise estimate of the density is thus crucial to decide if a novel energetic material is worth pursuing. In this work we investigate ... -
A Critical Investigation of Proposed Electrostatic Corrections to Quantum Mechanical Volumes: The Importance of Variation and the Irrelevance of Imbalance
Kjønstad, Eirik; Moxnes, John Fredrik; Jensen, Tomas Lunde; Unneberg, Erik (2016)The crystal density of neutral and ionic molecular crystals is remarkably well approximated by the enclosed volume of molecular surfaces, where these surfaces are defined as regions of constant and small electron density. ... -
Experimental and numerical study of the fragmentation of expanding warhead casings by using different numerical codes and solution techniques
Moxnes, John Fredrik; Prytz, Anne K.; Frøyland, Øyvind; Klokkehaug, Siri; Skriudalen, Stian; Friis, Eva; Teland, Jan Arild; Dørum, Cato; Ødegårdstuen, Gard (2014)There has been increasing interest in numerical simulations of fragmentation of expanding warheads in 3D. Accordingly there is a pressure on developers of leading commercial codes, such as LS-DYNA, AUTODYN and IMPETUS Afea, ... -
Introducing Randomness into First-Order and Second-Order Deterministic Differential Equations
Moxnes, John Fredrik; Hausken, Kjell (2010)We incorporate randomness into deterministic theories and compare analytically and numerically some well-known stochastic theories: the Liouville process, the Ornstein-Uhlenbeck process, and a process that is Gaussian and ... -
The kinetics of lactate production and removal during whole-body exercise
Moxnes, John Fredrik; Sandbakk, Øyvind (2012-03-13)Background Based on a literature review, the current study aimed to construct mathematical models of lactate production and removal in both muscles and blood during steady state and at varying intensities during whole-body ... -
Mathematical modelling of the oxygen uptake kinetics during whole-body endurance exercise and recovery
Moxnes, John Fredrik; Sandbakk, Øyvind (2017)In this study, we elucidate four different mathematical models of the kinetics of oxygen uptake during whole-body endurance exercise at different intensities and throughout the subsequent recovery periods. We employ the ... -
Mathematical relations related to the lode parameter for studies of ductility
Moxnes, John Fredrik; Frøyland, Øyvind (2016)During plastic flow, hydrostatic pressure and plastic strain control the size of the yield surface while the Lode angle is responsible for its shape. The von Mises yield condition shows no dependency of the Lode angle ... -
Mathematical simulation of enegy expenditure and recovery during sprint cross-country skiing
Moxnes, John Fredrik; Moxnes, Eldbjørg Dirdal (2014)Purpose: A cross-country sprint competition relies on maximal effort durations of 3–4 minutes. Significant anaerobic energy contribution is expected. Anaerobic energy contribution has been estimated in different sports to ... -
Methicillin-Resistant Staphylococcus aureus (MRSA) Is Increasing in Norway: A Time Series Analysis of Reported MRSA and Methicillin-Sensitive S. aureus Cases, 1997–2010
Moxnes, John Fredrik; De Blasio, Birgitte Freiesleben; Leegaard, Truls Michael; Moen, Aina Elisabeth Fossum (2013)The current study simulated cross-country skiing on varying terrain by using a power balance model. By applying the hypothetical inductive deductive method, we compared the simulated position along the track with actual ... -
Micro indentation hardness testing of commercial-grade RDX crystals
Moxnes, John Fredrik; Frøyland, Øyvind; Olsen, Torbjørn; Jensen, Tomas Lunde; Unneberg, Erik (2016)This paper describes the continuous micro indentation hardness testing of two commercial grades of RDX with differing shock sensitivities using three (3) different loads on a Berkovich indenter to obtain values of elastic ... -
Models for predicting impact sensitivity of energetic materials based on the trigger linkage hypothesis and Arrhenius kinetics
Jensen, Tomas Lunde; Moxnes, John Fredrik; Unneberg, Erik; Christensen, Dennis (2020)In order to predict the impact sensitivity of high explosives, we designed and evaluated several models based on the trigger linkage hypothesis and the Arrhenius equation. To this effect, we calculated the heat of detonation, ... -
On the Big Bang Cosmology as a Kinematic Event in Newtonian Cosmology Modified by Dark Energy
Moxnes, John Fredrik; Hausken, Kjell (2012)The concepts dark matter and dark energy are commonly used to explain the universe. The dark energy can be conceived as a property of vacuum or the ether. However, a quite different but also common approach is to modify ... -
On the Kinetics of Anaerobic Power
Moxnes, John Fredrik; Hausken, Kjell; Sandbakk, Øyvind (2012)Background This study investigated two different mathematical models for the kinetics of anaerobic power. Model 1 assumes that the work power is linear with the work rate, while Model 2 assumes a linear relationship ... -
On the study of ricochet and penetration in sand, water and gelatin by spheres, 7.62 mm APM2, and 25?mm projectiles
Moxnes, John Fredrik; Frøyland, Øyvind; Skriudalen, Stian; Prytz, Anne K.; Teland, Jan Arild; Friis, Eva; Ødegårdstuen, Gard (2016)We examine the ricochet and penetration behavior in sand, water and gelatin by steel spheres, 7.62 mm APM2 and 25 mm projectiles. A threshold impact angle (critical angle) exists beyond which ricochet cannot occur. The ... -
Projected area and drag coefficient of high velocity irregular fragments that rotate or tumble
Moxnes, John Fredrik; Frøyland, Øyvind; Øye, Ivar Jarle; Brate, Tom I.; Friis, Eva; Ødegårdstuen, Gard; Risdal, Tallak Harald (2017)3 degrees of freedom (DOF) exterior ballistic computer models are used in fragment studies to calculate individual trajectories of each fragment based on drag coefficient and the projected (presented) area in the direction ... -
A simulation of cross-country skiing on varying terrain by using a mathematical power balance model
Moxnes, John Fredrik; Sandbakk, Øyvind; Hausken, Kjell (2013)The current study simulated cross-country skiing on varying terrain by using a power balance model. By applying the hypothetical inductive deductive method, we compared the simulated position along the track with actual ... -
Simulation of natural fragmentation of rings cut from warheads
Moxnes, John Fredrik; Børve, Steinar (2015)Natural fragmentation of warheads that detonates causes the casing of the warhead to split into various sized fragments through shear or radial fractures depending on the toughness, density, and grain size of the material. ...