3D Servicescape Model: Atmospheric Qualities of Virtual Reality Retailing
Aasim Munir Dad
2016-02-01
Full Text Available The purpose of this paper is to provide a 3D servicescape conceptual model which explores the potential effect of 3D virtual reality retail stores’ environment on shoppers' behaviour. Extensive review of literature within two different domains, namely: servicescape models, and retail atmospherics, was carried out in order to propose a conceptual model. Further, eight detailed interviews were conducted to confirm the stimulus dimension of the conceptual model. A 3D servicescape conceptual model is offered on the basis of stimulus-organism-dimension, which proposes that a 3D virtual reality retail (VRR store environment consists of physical, social, socially symbolic and natural dimensions. These dimensions are proposed to affect shoppers’ behaviour through the mediating variables of emotions (pleasure and arousal. An interrelationship between pleasure and arousal, as mediating variables, is also proposed. This research opens a number of new avenues for further research through the proposed model of shoppers’ behaviour in a VRR store environment. Further, a systematic taxonomy development of VRR store environment is attempted through this proposed model that may prove to be an important step in theory building. A comprehensive 3D service scape model along with a large number of propositions is made to define a 3D VRR store environment.
Limb darkening laws for two exoplanet host stars derived from 3D stellar model atmospheres
Hayek, W; Pont, F; Asplund, M
2012-01-01
We compare limb darkening laws derived from 3D hydrodynamical model atmospheres and 1D hydrostatic MARCS models for the host stars of the two transiting exoplanet systems HD 209458 and HD 189733. The surface brightness distribution of the stellar disks is calculated using 3D LTE spectrum formation and opacity sampling. We test our predictions using least-squares fits of model light curves to primary eclipses that were observed with the Hubble Space Telescope (HST). The limb darkening law derived from the 3D model of HD 209458 between 2900 A and 5700 A produces significantly better fits to the HST data, removing systematic residuals that were previously observed for model light curves based on 1D predictions. This difference arises mainly from the shallower mean temperature structure of the 3D model, which is a consequence of the explicit simulation of surface granulation. In the case of HD 189733, the model atmospheres produce practically equivalent limb darkening curves between 2900 A and 5700 A, partly due ...
Validation of 3-D CFD Model of Tritium Transport in the Atmosphere
When solving 3-D problems for the atmospheric impurity transport in the bounded area, it is essential for the atmospheric dynamics to be correctly computed taking into account the actual terrain topography and environments specified by the boundary conditions. Such conditions as turbulence, convection, condensation and moisture evaporation processes, etc. are to be also taken into account as well as the interaction processes among impurities (gases, aerosols), atmosphere and the Earth's surface.3-D computational fluid dynamics model(CFD) developed on the basis of SRP hydrodynamic code was used to simulate tritium plume evolution and tritium transport in atmosphere under the area with relatively complex topography. SRP code is based on the continuum motion equations (Navier-Stockes equations) and thermodynamic relations taking into account specific features of atmospheric flows and complex topography and is designed to use on PC-type computers.The model has been validated using experimental release of tritium with specified source term and meteorology. Due to low release height above the underlying surface a fine grid was used in the vertical direction near the underlying surface. HT and HTO/H2O vertical fluxes were taken into account. Evolution of HT and HTO activities at 2 sampling locations along the plume axe were available for model-experiment inter-comparison. The modeling results of HT and HTO activities in the air during plume travel are in satisfactory agreement with observed values
Solar Chemical Abundances Determined with a CO5BOLD 3D Model Atmosphere
Caffau, Elisabetta; Steffen, Matthias; Freytag, Bernd; Bonifacio, Piercarlo
2010-01-01
In the last decade, the photospheric solar metallicity as determined from spectroscopy experienced a remarkable downward revision. Part of this effect can be attributed to an improvement of atomic data and the inclusion of NLTE computations, but also the use of hydrodynamical model atmospheres seemed to play a role. This "decrease" with time of the metallicity of the solar photosphere increased the disagreement with the results from helioseismology. With a CO5BOLD 3D model of the solar atmosphere, the CIFIST team at the Paris Observatory re-determined the photospheric solar abundances of several elements, among them C, N, and O. The spectroscopic abundances are obtained by fitting the equivalent width and/or the profile of observed spectral lines with synthetic spectra computed from the 3D model atmosphere. We conclude that the effects of granular fluctuations depend on the characteristics of the individual lines, but are found to be relevant only in a few particular cases. 3D effects are not reponsible for t...
Solar Chemical Abundances Determined with a CO5BOLD 3D Model Atmosphere
Caffau, E.; Ludwig, H.-G.; Steffen, M.; Freytag, B.; Bonifacio, P.
2011-02-01
In the last decade, the photospheric solar metallicity as determined from spectroscopy experienced a remarkable downward revision. Part of this effect can be attributed to an improvement of atomic data and the inclusion of NLTE computations, but also the use of hydrodynamical model atmospheres seemed to play a role. This "decrease" with time of the metallicity of the solar photosphere increased the disagreement with the results from helioseismology. With a CO 5 BOLD 3D model of the solar atmosphere, the CIFIST team at the Paris Observatory re-determined the photospheric solar abundances of several elements, among them C, N, and O. The spectroscopic abundances are obtained by fitting the equivalent width and/or the profile of observed spectral lines with synthetic spectra computed from the 3D model atmosphere. We conclude that the effects of granular fluctuations depend on the characteristics of the individual lines, but are found to be relevant only in a few particular cases. 3D effects are not responsible for the systematic lowering of the solar abundances in recent years. The solar metallicity resulting from this analysis is Z=0.0153, Z/ X=0.0209.
3D cut-cell modelling for high-resolution atmospheric simulations
Yamazaki, H; Nikiforakis, N
2015-01-01
With the recent, rapid development of computer technology, the resolution of atmospheric numerical models has increased substantially. As a result, steep gradients in mountainous terrain are now being resolved in high-resolution models. This results in large truncation errors in those models using terrain-following coordinates. In this study, a new 3D Cartesian coordinate non-hydrostatic atmospheric model is developed. A cut-cell representation of topography based on finite-volume discretization is combined with a cell-merging approach, in which small cut-cells are merged with neighboring cells either vertically or horizontally. In addition, a block-structured mesh-refinement technique achieves a variable resolution on the model grid with the finest resolution occurring close to the terrain surface. The model successfully reproduces a flow over a 3D bell-shaped hill that shows a good agreement with the flow predicted by the linear theory. The ability of the model to simulate flows over steep terrain is demons...
Partial redistribution in 3D non-LTE radiative transfer in solar atmosphere models
Sukhorukov, Andrii V
2016-01-01
Resonance spectral lines such as H I Ly {\\alpha}, Mg II h&k, and Ca II H&K that form in the solar chromosphere are influenced by the effects of 3D radiative transfer as well as partial redistribution (PRD). So far no one has modeled these lines including both effects simultaneously owing to the high computing demands of existing algorithms. Such modeling is however indispensable for accurate diagnostics of the chromosphere. We present a computationally tractable method to treat PRD scattering in 3D model atmospheres using a 3D non-LTE radiative transfer code. To make the method memory-friendly, we use the hybrid approximation of Leenaarts et al. (2012) for the redistribution integral. To make it fast, we use linear interpolation on equidistant frequency grids. We verify our algorithm against computations with the RH code and analyze it for stability, convergence, and usefulness of acceleration using model atoms of Mg II with the h&k lines and H I with the Ly {\\alpha} line treated in PRD. A typical...
Use of coupled ozone fields in a 3-D circulation model of the middle atmosphere
T. Reddmann
Full Text Available With a detailed chemistry scheme for the middle atmosphere up to 70 km which has been added to the 3-D Karlsruhe simulation model of the middle atmosphere (KASIMA, the effects of coupling chemistry and dynamics through ozone are studied for the middle atmosphere. An uncoupled version using an ozone climatology for determining heating rates and a coupled version using on-line ozone are compared in a 10-month integration with meteorological analyses for the winter 1992/93 as the lower boundary condition. Both versions simulate the meteorological situation satisfactorily, but exhibit a too cold lower stratosphere. The on-line ozone differs from the climatological data between 20 and 40 km by exhibiting too high ozone values, whereas in the lower mesosphere the ozone values are too low. The coupled model version is stable and differs only above 40 km significantly from the uncoupled version. Direct heating effects are identified to cause most of the differences. The well-known negative correlation between temperature and ozone is reproduced in the model. As a result, the coupled version slightly approaches the climatological ozone field. Further feedback effects are studied by using the on-line ozone field as a basis for an artificial climatology. For non-disturbed ozone conditions realistic monthly and zonally averaged ozone data are sufficient to determine the heating rates for modelling the middle atmosphere.
Key words. Atmospheric composition and structure (middle atmosphere · composition and chemistry · Meteorology and atmospheric dynamics (middle atmosphere dynamics.
Charnay, Benjamin; Misra, Amit; Leconte, Jérémy; Arney, Giada
2015-01-01
The warm sub-Neptune GJ1214b has a featureless transit spectrum which may be due to the presence of high and thick clouds or haze. Here, we simulate the atmosphere of GJ1214b with a 3D General Circulation Model for cloudy hydrogen-dominated atmospheres, including cloud radiative effects. We show that the atmospheric circulation is strong enough to transport micrometric cloud particles to the upper atmosphere and generally leads to a minimum of cloud at the equator. By scattering stellar light, clouds increase the planetary albedo to 0.4-0.6 and cool the atmosphere below 1 mbar. However, the heating by ZnS clouds leads to the formation of a stratospheric thermal inversion above 10 mbar, with temperatures potentially high enough on the dayside to evaporate KCl clouds. We show that flat transit spectra consistent with HST observations are possible if cloud particle radii are around 0.5 micron, and that such clouds should be optically thin at wavelengths > 3 microns. Using simulated cloudy atmospheres that fit th...
Non-LTE oxygen line formation in 3D hydrodynamic model stellar atmospheres
Amarsi, A M; Collet, R; Leenaarts, J
2015-01-01
The OI 777 nm lines are among the most commonly used diagnostics for the oxygen abundances in the atmospheres of FGK-type stars. However, they form in conditions that are far from local thermodynamic equilibrium (LTE). We explore the departures from LTE of atomic oxygen, and their impact on OI lines, across the Stagger-grid of three-dimensional hydrodynamic model atmospheres. For the OI 777 nm triplet we find significant departures from LTE. These departures are larger in stars with larger effective temperatures, smaller surface gravities, and larger oxygen abundances. We present grids of predicted 3D non-LTE based equivalent widths for the OI616nm, [OI] 630 nm, [OI] 636 nm, and OI 777 nm lines, as well as abundance corrections to 1D LTE based results.
Numerical modelling of pollution dispersion in 3D atmospheric boundary layer
Benes, L.; Bodnar, T.; Kozel, K. [Czech Technical Univ. of Prague (Czech Republic). Dept. of Technical Mathematics; Fraunie, Ph. [Univ. de Toulon et du Var, La Garde (France). Lab. de Sondages Electromagnetiques et Environnemental Terrestre
2002-07-01
The main goal of this work is to present the applicable models and numerical methods for solution of flow and pollution dispersion in 3D atmospheric boundary layer (ABL). Mathematical models are based on the system of Reynolds averaged Navier-Stokes equations and its simplifications. The sets of governing equations are completed by the transport equations for passive impurities and potential temperature. A simple algebraic turbulent closure model is used. The thermal stability phenomenon is taken into account. For each mathematical model a numerical scheme based on finite-difference or finite-volume discretization is proposed and discussed. Some results of numerical tests are presented for pollution dispersion from point sources and flows over simple geometries. (orig.)
The Solar Photospheric Oxygen Abundance and the Role of 3D Model Atmospheres
Caffau, E.; Steffen, M.; Ludwig, H.-G.
2008-09-01
The solar oxygen abundance has undergone a major downward revision in the last decade, reputedly as a result of employing 3D hydrodynamical simulations to model the inhomogeneous structure of the solar photosphere. The very low oxygen abundance advocated by Asplund et al. 2004, A(O)=8.66, together with the downward revision of the abundances of other key elements, has created serious problems for solar models to explain the helioseismic measurements. In an effort to contribute to the dispute of whether the Sun has "solar" or "sub-solar" abundances, we have re-derived its photospheric abundance of oxygen, nitrogen, and other elements, independently of previous analyses. We applied a state-of-the art 3D (CO5BOLD) hydrodynamical simulation of the solar granulation as well as different 1D model atmospheres for the line by line spectroscopic abundance determinations. The analysis is based on both standard disk-center and full-disk spectral atlases; for oxygen we acquired in addition spectra at different heliocentric angles. The derived abundances are the result of equivalent width and/or line profile fitting of the available atomic lines. Our recommended oxygen abundance is A(O)=8.76+- 0.07, 0.1 dex higher than the value of Asplund et al. (2004). Our current estimate of the overall solar metallicity is 0.014< Z<0.016. Questions we discuss include: (i) Is the general downward revision of the solar abundances a 3D effect? (ii) How large are the abundance corrections due to horizontal inhomogeneities? (iii) What is the main reason for the differences between the abundances obtained in our study and those derived by Apslund and coworkers? (iv) How large are the uncertainties in the observed solar spectra? (v) What is the reason why the two forbidden oxygen lines, [OI] lambda 630 nm and [OI] lambda 636.3 nm, give significantly different answers for the solar oxygen abundance?
Titan's past and future: 3D modeling of a pure nitrogen atmosphere and geological implications
Charnay, Benjamin; Tobie, Gabriel; Sotin, Christophe; Wordsworth, Robin
2014-01-01
Several clues indicate that Titan's atmosphere has been depleted in methane during some period of its history, possibly as recently as 0.5-1 billion years ago. It could also happen in the future. Under these conditions, the atmosphere becomes only composed of nitrogen with a range of temperature and pressure allowing liquid or solid nitrogen to condense. Here, we explore these exotic climates throughout Titan's history with a 3D Global Climate Model (GCM) including the nitrogen cycle and the radiative effect of nitrogen clouds. We show that for the last billion years, only small polar nitrogen lakes should have formed. Yet, before 1 Ga, a significant part of the atmosphere could have condensed, forming deep nitrogen polar seas, which could have flowed and flooded the equatorial regions. Alternatively, nitrogen could be frozen on the surface like on Triton, but this would require an initial surface albedo higher than 0.65 at 4 Ga. Such a state could be stable even today if nitrogen ice albedo is higher than th...
Hundebøl, Jesper
wave of new building information modelling tools demands further investigation, not least because of industry representatives' somewhat coarse parlance: Now the word is spreading -3D digital modelling is nothing less than a revolution, a shift of paradigm, a new alphabet... Research qeustions. Based...... on empirical probes (interviews, observations, written inscriptions) within the Danish construction industry this paper explores the organizational and managerial dynamics of 3D Digital Modelling. The paper intends to - Illustrate how the network of (non-)human actors engaged in the promotion (and arrest) of 3......D Modelling (in Denmark) stabilizes - Examine how 3D Modelling manifests itself in the early design phases of a construction project with a view to discuss the effects hereof for i.a. the management of the building process. Structure. The paper introduces a few, basic methodological concepts...
Hejlesen, Aske K.; Ovesen, Nis
2012-01-01
This paper presents an experimental approach to teaching 3D modelling techniques in an Industrial Design programme. The approach includes the use of tangible free form models as tools for improving the overall learning. The paper is based on lecturer and student experiences obtained through...
The StaggerGrid Project: a Grid of 3D Model Atmospheres for High-Precision Spectroscopy
Collet, Remo; Asplund, Martin
2011-01-01
In this contribution, we present the StaggerGrid, a collaborative project for the construction of a comprehensive grid of time-dependent, three-dimensional (3D), hydrodynamic model atmospheres of solar- and late-type stars with different effective temperatures, surface gravities, and chemical compositions. We illustrate the main characteristics of these 3D models and their effects on the predicted strengths, wavelength-shifts, and shapes of spectral lines, highlighting the differences with respect to calculations based on classical, one-dimensional, hydrostatic models, and discuss some of their possible applications to elemental abundance analysis of stellar spectra in the context of large observational surveys.
Loukitcheva, Maria; Carlsson, Mats; White, Stephen
2015-01-01
Aims. We use advanced 3D NLTE radiative magnetohydrodynamic simulations of the solar atmosphere to carry out detailed tests of chromospheric diagnostics at millimeter and submillimeter wavelengths. Methods. We focused on the diagnostics of the thermal structure of the chromosphere in the wavelength bands from 0.4 mm up to 9.6 mm that can be accessed with the Atacama Large Millimeter/Submillimeter Array (ALMA) and investigated how these diagnostics are affected by the instrumental resolution. Results. We find that the formation height range of the millimeter radiation depends on the location in the simulation domain and is related to the underlying magnetic structure. Nonetheless, the brightness temperature is a reasonable measure of the gas temperature at the effective formation height at a given location on the solar surface. There is considerable scatter in this relationship, but this is significantly reduced when very weak magnetic fields are avoided. Our results indicate that although instrumental smearin...
On line contribution functions and examining spectral line formation in 3D model stellar atmospheres
Amarsi, Anish Mayur
2015-01-01
Line contribution functions are useful diagnostics for studying spectral line formation in stellar atmospheres. I derive an expression for the contribution function to the abso- lute flux depression that emerges from three-dimensional box-in-a-star model stellar atmospheres. I illustrate the result by comparing the local thermodynamic equilibrium (LTE) spectral line formation of the high-excitation permitted OI777nm lines with the non-LTE case.
Evaluating Satellite Observed CO2 Column by a 3-D Atmospheric Transport Model
Satellite remote sensing is the latest method of measuring atmospheric CO2, which covers a wide range and makes periodic observation. But due to lack of ground-based observation sites, global satellite observed CO2 column is not evaluated efficiently. This paper assess the applicability of using GEOS-Chem model to forward simulate atmospheric CO2 for verifying Greenhouse Gas Observation SATellite (GOSAT) observed CO2 column. It is shown that GEOS-Chem performs well in modelling atmospheric CO2 and there are generally no significant differences between ground-based observation and model results. According to the comparsion, the spatial and temporal distribution of XCO2 agrees well between GOSAT and GEOS-Chem. GOSAT XCO2 is turned out to be 2.6 ppm lower than the model results. The mean difference observed between GOSAT and GEOS-Chem varies from −1.8 to −3.1 ppm seasonally, with the standard deviation ranging from 1.4 to 2.1 ppm. And in general, the difference is larger in summer than that in winter, in land area than in sea area. It might have been caused by the different land-sea distribution and eco-system's changing with seasons
Assessing the habitability of planets with Earth-like atmospheres with 1D and 3D climate modeling
Godolt, M.; Grenfell, J. L.; Kitzmann, D.; Kunze, M.; Langematz, U.; Patzer, A. B. C.; Rauer, H.; Stracke, B.
2016-07-01
Context. The habitable zone (HZ) describes the range of orbital distances around a star where the existence of liquid water on the surface of an Earth-like planet is in principle possible. The applicability of one-dimensional (1D) climate models for the estimation of the HZ boundaries has been questioned by recent three-dimensional (3D) climate studies. While 3D studies can calculate the water vapor, ice albedo, and cloud feedback self-consistently and therefore allow for a deeper understanding and the identification of relevant climate processes, 1D model studies rely on fewer model assumptions and can be more easily applied to the large parameter space possible for extrasolar planets. Aims: We evaluate the applicability of 1D climate models to estimate the potential habitability of Earth-like extrasolar planets by comparing our 1D model results to those of 3D climate studies in the literature. We vary the two important planetary properties, surface albedo and relative humidity, in the 1D model. These depend on climate feedbacks that are not treated self-consistently in most 1D models. Methods: We applied a cloud-free 1D radiative-convective climate model to calculate the climate of Earth-like planets around different types of main-sequence stars with varying surface albedo and relative humidity profile. We compared the results to those of 3D model calculations available in the literature and investigated to what extent the 1D model can approximate the surface temperatures calculated by the 3D models. Results: The 1D parameter study results in a large range of climates possible for an Earth-sized planet with an Earth-like atmosphere and water reservoir at a certain stellar insolation. At some stellar insolations the full spectrum of climate states could be realized, i.e., uninhabitable conditions due to surface temperatures that are too high or too low as well as habitable surface conditions, depending only on the relative humidity and surface albedo assumed. When
Petry, H.; Ebel, A.; Franzkowiak, V.; Hendricks, J.; Lippert, E.; Moellhoff, M. [Koeln Univ. (Germany). Inst. fuer Geophysik und Meteorologie
1997-12-31
The impact of aircraft emissions released in the tropopause region on atmospheric trace gases as O{sub 3} or HNO{sub 3} is investigated by means of model studies. Special emphasis is drawn on seasonal effects. A box model is applied as well as a 3-D mesoscale chemistry transport model. These model studies show that the impact of aircraft emissions on ozone in the tropopause region is much stronger in summer than in late autumn with a difference of one order of magnitude. (author) 14 refs.
Magic, Zazralt; Asplund, Martin
2014-01-01
We investigate the relation between 1D atmosphere models that rely on the mixing length theory and models based on full 3D radiative hydrodynamic (RHD) calculations to describe convection in the envelopes of late-type stars. The adiabatic entropy value of the deep convection zone, s_bot, and the entropy jump, {\\Delta}s, determined from the 3D RHD models, are matched with the mixing length parameter, {\\alpha}_MLT, from 1D hydrostatic atmosphere models with identical microphysics (opacities and equation-of-state). We also derive the mass mixing length, {\\alpha}_m, and the vertical correlation length of the vertical velocity, C[v_z,v_z], directly from the 3D hydrodynamical simulations of stellar subsurface convection. The calibrated mixing length parameter for the Sun is {\\alpha}_MLT (s_bot) = 1.98. For different stellar parameters, {\\alpha}_MLT varies systematically in the range of 1.7 - 2.4. In particular, {\\alpha}_MLT decreases towards higher effective temperature, lower surface gravity and higher metallicity...
Process analysis of the modelled 3-D mesoscale impact of aircraft emissions on the atmosphere
Hendricks, J.; Ebel, A.; Lippert, E.; Petry, H. [Koeln Univ. (Germany). Inst. fuer Geophysik und Meterorologie
1997-12-31
A mesoscale chemistry transport model is applied to study the impact of aircraft emissions on the atmospheric trace gas composition. A special analysis of the simulations is conducted to separate the effects of chemistry, transport, diffusion and cloud processes on the transformation of the exhausts of a subsonic fleet cruising over the North Atlantic. The aircraft induced ozone production strongly depends on the tropopause height and the cruise altitude. Aircraft emissions may undergo an effective downward transport under the influence of stratosphere-troposphere exchange activity. (author) 12 refs.
3D modeling of GJ1214b's atmosphere: vertical mixing driven by an anti-Hadley circulation
Charnay, Benjamin; Leconte, Jérémy
2015-01-01
GJ1214b is a warm sub-Neptune transiting in front of a nearby M dwarf star. Recent observations indicate the presence of high and thick clouds or haze whose presence requires strong atmospheric mixing. In order to understand the transport and distribution of such clouds/haze, we study the atmospheric circulation and the vertical mixing of GJ1214b with a 3D General Circulation Model for cloud-free hydrogen-dominated atmospheres (metallicity of 1, 10 and 100 times the solar value) and for a water-dominated atmosphere. We analyze the effect of the atmospheric metallicity on the thermal structure and zonal winds. We also analyze the zonal mean meridional circulation and show that it corresponds to an anti-Hadley circulation in most of the atmosphere with upwelling at mid-latitude and downwelling at the equator in average. This circulation must be present on a large range of synchronously rotating exoplanets with strong impact on cloud formation and distribution. Using simple tracers, we show that vertical winds o...
Forget, Francois; Millour, Ehouarn; Madeleine, Jean-Baptiste; Kerber, Laura; Leconte, Jeremy; Marcq, Emmanuel; Haberle, Robert M
2012-01-01
On the basis of geological evidence, it is often stated that the early martian climate was warm enough for liquid water to flow on the surface thanks to the greenhouse effect of a thick atmosphere. We present 3D global climate simulations of the early martian climate performed assuming a faint young sun and a CO2 atmosphere with pressure between 0.1 and 7 bars. The model includes a detailed radiative transfer model using revised CO2 gas collision induced absorption properties, and a parameterisation of the CO2 ice cloud microphysical and radiative properties. A wide range of possible climates is explored by using various values of obliquities, orbital parameters, cloud microphysic parameters, atmospheric dust loading, and surface properties. Unlike on present day Mars, for pressures higher than a fraction of a bar, surface temperatures vary with altitude because of the adiabatic cooling and warming of the atmosphere when it moves vertically. In most simulations, CO2 ice clouds cover a major part of the planet...
6Li detection in metal-poor stars: can 3D model atmospheres solve the second lithium problem?
Steffen, M; Caffau, E; Bonifacio, P; Ludwig, H -G; Spite, M
2012-01-01
The presence of 6Li in the atmospheres of metal-poor halo stars is usually inferred from the detection of a subtle extra depression in the red wing of the 7Li doublet line at 670.8 nm. However, the intrinsic line asymmetry caused by convective flows in the photospheres of cool stars is almost indistinguishable from the asymmetry produced by a weak 6Li blend on a (presumed) symmetric 7Li profile. Previous determinations of the 6Li/ 7Li isotopic ratio based on 1D model atmospheres, ignoring the convection-induced line asymmetry, must therefore be considered as upper limits. By comparing synthetic 1D LTE and 3D non-LTE line profiles of the Li 670.8 nm feature, we quantify the differential effect of the convective line asymmetry on the derived 6Li abundance as a function of effective temperature, gravity, and metallicity. As expected, we find that the asymmetry effect systematically reduces the resulting 6Li/7Li ratios. Depending on the stellar parameters, the 3D-1D offset in 6Li/7Li ranges between -0.005 and -0....
Rodrigues, Marcos; Robinson, Alan; Alboul, Lyuba; Brink, Willie
2006-01-01
3D face recognition is an open field. In this paper we present a method for 3D facial recognition based on Principal Components Analysis. The method uses a relatively large number of facial measurements and ratios and yields reliable recognition. We also highlight our approach to sensor development for fast 3D model acquisition and automatic facial feature extraction.
Magic, Zazralt
2014-01-01
In the surface layers of late-type stars, stellar convection is manifested with its typical granulation pattern due to the presence of convective motions. The resulting photospheric up- and downflows leave imprints in the observed spectral line profiles. We perform a careful statistical analysis of stellar granulation and its properties for different stellar parameters. We employ realistic 3D radiative hydrodynamic (RHD) simulations of surface convection from the Stagger-grid, a comprehensive grid of atmosphere models that covers a large parameter space in terms of Teff, logg, and [Fe/H]. Individual granules are detected from the (bolometric) intensity maps at disk center with an efficient granulation pattern recognition algorithm. From these we derive their respective properties: diameter, fractal dimension (area-perimeter relation), geometry, topology, variation of intensity, temperature, density and velocity with granule size. Also, the correlation of the physical properties at the optical surface are stud...
I. V. Mingalev
2006-09-01
Full Text Available We present the first results of a 3-D General Circulation Model of Titan's atmosphere which differs from traditional models in that the hydrostatic equation is not used and all three components of the neutral gas velocity are obtained from the numerical solution of the Navier-Stokes equation. The current version of our GCM is, however, a simplified version, as it uses a predescribed temperature field in the model region thereby avoiding the complex simulation of radiative transfer based on the energy equation. We present the first simulation results and compare them to the results of existing GCMs and direct wind observations. The wind speeds obtained from our GCM correspond well with data obtained during the Huygens probe descent through Titan's atmosphere. We interpret the most unexpected feature of these data which consist of the presence of a non-monotonicity of the altitude profile of the zonal wind speed between 60 and 75 km.
Development of a 3D Soil-Plant-Atmosphere Continuum (SPAC) coupled to a Land Surface Model
Bisht, G.; Riley, W. J.; Lorenzetti, D.; Tang, J.
2015-12-01
Exchange of water between the atmosphere and biosphere via evapotranspiration (ET) influences global hydrological, energy, and biogeochemical cycles. Isotopic analysis has shown that evapotranspiration over the continents is largely dominated by transpiration. Water is taken up from soil by plant roots, transported through the plant's vascular system, and evaporated from the leaves. Yet current Land Surface Models (LSMs) integrated into Earth System Models (ESMs) treat plant roots as passive components. These models distribute the ET sink vertically over the soil column, neglect the vertical pressure distribution along the plant vascular system, and assume that leaves can directly access water from any soil layer within the root zone. Numerous studies have suggested that increased warming due to climate change will lead drought and heat-induced tree mortality. A more mechanistic treatment of water dynamics in the soil-plant-atmosphere continuum (SPAC) is essential for investigating the fate of ecosystems under a warmer climate. In this work, we describe a 3D SPAC model that can be coupled to a LSM. The SPAC model uses the variably saturated Richards equations to simulate water transport. The model uses individual governing equations and constitutive relationships for the various SPAC components (i.e., soil, root, and xylem). Finite volume spatial discretization and backward Euler temporal discretization is used to solve the SPAC model. The Portable, Extensible Toolkit for Scientific Computation (PETSc) is used to numerically integrate the discretized system of equations. Furthermore, PETSc's multi-physics coupling capability (DMComposite) is used to solve the tightly coupled system of equations of the SPAC model. Numerical results are presented for multiple test problems.
Arroyo-Torres, B; Chiavassa, A; Scholz, M; Freytag, B; Marcaide, J M; Hauschildt, P H; Wood, P R; Abellan, F J
2015-01-01
We present the atmospheric structure and the fundamental parameters of three red supergiants, increasing the sample of RSGs observed by near-infrared spectro-interferometry. Additionally, we test possible mechanisms that may explain the large observed atmospheric extensions of RSGs. We carried out spectro-interferometric observations of 3 RSGs in the near-infrared K-band with the VLTI/AMBER instrument at medium spectral resolution. To comprehend the extended atmospheres, we compared our observational results to predictions by available hydrostatic PHOENIX, available 3-D convection, and new 1-D self-excited pulsation models of RSGs. Our near-infrared flux spectra are well reproduced by the PHOENIX model atmospheres. The continuum visibility values are consistent with a limb-darkened disk as predicted by the PHOENIX models, allowing us to determine the angular diameter and the fundamental parameters of our sources. Nonetheless, in the case of V602 Car and HD 95686, the PHOENIX model visibilities do not predict ...
Lading, Brian; Larsen, Rasmus; Åström, Kalle
2006-01-01
We build a 3d face shape model, including inter- and intra-shape variations, derive the analytical jacobian of its resulting 2d rendered image, and show example of its fitting performance with light, pose, id, expression and texture variations.}......We build a 3d face shape model, including inter- and intra-shape variations, derive the analytical jacobian of its resulting 2d rendered image, and show example of its fitting performance with light, pose, id, expression and texture variations.}...
Lading, Brian; Larsen, Rasmus; Astrom, K
2006-01-01
We build a 3D face shape model, including inter- and intra-shape variations, derive the analytical Jacobian of its resulting 2D rendered image, and show example of its fitting performance with light, pose, id, expression and texture variations......We build a 3D face shape model, including inter- and intra-shape variations, derive the analytical Jacobian of its resulting 2D rendered image, and show example of its fitting performance with light, pose, id, expression and texture variations...
Manos, Harry
2016-01-01
Visual aids are important to student learning, and they help make the teacher's job easier. Keeping with the "TPT" theme of "The Art, Craft, and Science of Physics Teaching," the purpose of this article is to show how teachers, lacking equipment and funds, can construct a durable 3-D model reference frame and a model gravity…
2007-01-01
The results of four gas tracer experiments of atmospheric dispersion on a regional scale are used for the benchmarking of two atmospheric dispersion modeling codes, MINERVE-SPRAY (CEA), and NOSTRADAMUS (IBRAE). The main topic of this comparison is to estimate the Lagrangian code capability to predict the radionuclide atmospheric transfer on a large field, in the case of risk assessment of nuclear power plant for example. For the four experiments, the results of calculations show a rather...
Lading, Brian; Larsen, Rasmus; Åström, Kalle
2006-01-01
We build a 3d face shape model, including inter- and intra-shape variations, derive the analytical jacobian of its resulting 2d rendered image, and show example of its fitting performance with light, pose, id, expression and texture variations.}
Lading, Brian; Larsen, Rasmus; Astrom, K
2006-01-01
We build a 3D face shape model, including inter- and intra-shape variations, derive the analytical Jacobian of its resulting 2D rendered image, and show example of its fitting performance with light, pose, id, expression and texture variations
Assessing the habitability of planets with Earth-like atmospheres with 1D and 3D climate modeling
Godolt, M; Kitzmann, D; Kunze, M; Langematz, U; Patzer, A B C; Rauer, H; Stracke, B
2016-01-01
The habitable zone (HZ) describes the range of orbital distances around a star where the existence of liquid water on the surface of an Earth-like planet is in principle possible. While 3D climate studies can calculate the water vapor, ice albedo, and cloud feedback self-consistently and therefore allow for a deeper understanding and the identification of relevant climate processes, 1D model studies rely on fewer model assumptions and can be more easily applied to the large parameter space possible for exoplanets. We evaluate the applicability of 1D climate models to estimate the potential habitability of Earth-like exoplanets by comparing our 1D model results to those of 3D climate studies in the literature. We applied a cloud-free 1D radiative-convective climate model to calculate the climate of Earth-like planets around different types of main-sequence stars with varying surface albedo and relative humidity profile. These parameters depend on climate feedbacks that are not treated self-consistently in most...
A new Monte Carlo atmospheric radiative transfer model is presented which is designed to support the interpretation of UV/vis/near-IR spectroscopic measurements of scattered Sun light in the atmosphere. The integro differential equation describing the underlying transport process and its formal solution are discussed. A stochastic approach to solve the differential equation, the Monte Carlo method, is deduced and its application to the formal solution is demonstrated. It is shown how model photon trajectories of the resulting ray tracing algorithm are used to estimate functionals of the radiation field such as radiances, actinic fluxes and light path integrals. In addition, Jacobians of the former quantities with respect to optical parameters of the atmosphere are analyzed. Model output quantities are validated against measurements, by self-consistency tests and through inter comparisons with other radiative transfer models.
Manos, Harry
2016-03-01
Visual aids are important to student learning, and they help make the teacher's job easier. Keeping with the TPT theme of "The Art, Craft, and Science of Physics Teaching," the purpose of this article is to show how teachers, lacking equipment and funds, can construct a durable 3-D model reference frame and a model gravity well tailored to specific class lessons. Most of the supplies are readily available in the home or at school: rubbing alcohol, a rag, two colors of spray paint, art brushes, and masking tape. The cost of these supplies, if you don't have them, is less than 20.
Post processing of 3D models for 3D printing
Pikovnik, Tomaž
2015-01-01
According to the opinion of some experts the additive manufacturing or 3D printing will change manufacturing industry, because any individual could print their own model according to his or her wishes. In this graduation thesis some of the additive manufacturing technologies are presented. Furthermore in the production of house scale model in 1:100 is presented, starting from modeling to printing. Special attention is given to postprocessing of the building model elements us...
Sta. Maria, M.; Ketefian, G. S.; Jacobson, M. Z.
2010-12-01
In order to simulate better the effects of wind turbines on meteorology and climate, a parameterization based on the Blade Element Momentum (BEM) theory was developed and integrated into a high-resolution 3-D non-hydrostatic atmospheric model that conserves several domain-integrated quantities. The BEM model calculates the forces the blade exerts on the atmosphere and feeds it back as body forces in the momentum equations of the atmospheric model. Since the BEM method calculates these forces along a turbine blade, the parameterization allows for model spatial resolutions on the order of a few to tens of meters. This study examines the advantages and limitations of such a parameterization. The BEM calculates the rotational force that the blades exert on the air, and this study investigates whether this parameterization is able to capture rotation in the wake. The dependency on model resolution is also studied to determine the optimum model resolution for simulating wind turbine-atmosphere interactions. The atmospheric model is also used to estimate the distance downwind of a turbine at which wind speeds recover. This is an important parameter for determining optimal wind farm spacing. Model results will be compared with previous parameterizations and wake data gathered in the field and from wind tunnel studies.
François Van Dorpe
2007-01-01
Full Text Available The results of four gas tracer experiments of atmospheric dispersion on a regional scale are used for the benchmarking of two atmospheric dispersion modeling codes, MINERVE-SPRAY (CEA, and NOSTRADAMUS (IBRAE. The main topic of this comparison is to estimate the Lagrangian code capability to predict the radionuclide atmospheric transfer on a large field, in the case of risk assessment of nuclear power plant for example. For the four experiments, the results of calculations show a rather good agreement between the two codes, and the order of magnitude of the concentrations measured on the soil is predicted. Simulation is best for sampling points located ten kilometers from the source, while we note a divergence for more distant points results (difference in concentrations by a factor 2 to 5. This divergence may be explained by the fact that, for these four experiments, only one weather station (near the point source was used on a field of 10 000 km2, generating the simulation of a uniform wind field throughout the calculation domain.
The results of four gas tracer experiments of atmospheric dispersion on a regional scale are used for the benchmarking of two atmospheric dispersion modeling codes, MINERVE-SPRAY (CEA), and NOSTRADAMUS (IBRAE). The main topic of this comparison is to estimate the Lagrangian code capability to predict the radionuclide atmospheric transfer on a large field, in the case of risk assessment of nuclear power plant for example. For the four experiments, the results of calculations show a rather good agreement between the two codes, and the order of magnitude of the concentrations measured on the soil is predicted. Simulation is best for sampling points located ten kilometers from the source, while we note a divergence for more distant points results (difference in concentrations by a factor 2 to 5). This divergence may be explained by the fact that, for these four experiments, only one weather station (near the point source) was used on a field of 10000 km2, generating the simulation of a uniform wind field throughout the calculation domain.
Wang, Mian
This thesis research is consist of four chapters, including biomimetic three-dimensional tissue engineered nanostructured bone model for breast cancer bone metastasis study (Chapter one), cold atmospheric plasma for selectively ablating metastatic breast cancer (Chapter two), design of biomimetic and bioactive cold plasma modified nanostructured scaffolds for enhanced osteogenic differentiation of bone marrow derived mesenchymal stem cells (Chapter three), and enhanced osteoblast and mesenchymal stem cell functions on titanium with hydrothermally treated nanocrystalline hydroxyapatite/magnetically treated carbon nanotubes for orthopedic applications (Chapter four). All the thesis research is focused on nanomaterials and the use of cold plasma technique for various biomedical applications.
MT3D was first developed by Chunmiao Zheng in 1990 at S.S. Papadopulos & Associates, Inc. with partial support from the U.S. Environmental Protection Agency (USEPA). Starting in 1990, MT3D was released as a pubic domain code from the USEPA. Commercial versions with enhanced capab...
Crowdsourcing Based 3d Modeling
Somogyi, A.; Barsi, A.; Molnar, B.; Lovas, T.
2016-06-01
Web-based photo albums that support organizing and viewing the users' images are widely used. These services provide a convenient solution for storing, editing and sharing images. In many cases, the users attach geotags to the images in order to enable using them e.g. in location based applications on social networks. Our paper discusses a procedure that collects open access images from a site frequently visited by tourists. Geotagged pictures showing the image of a sight or tourist attraction are selected and processed in photogrammetric processing software that produces the 3D model of the captured object. For the particular investigation we selected three attractions in Budapest. To assess the geometrical accuracy, we used laser scanner and DSLR as well as smart phone photography to derive reference values to enable verifying the spatial model obtained from the web-album images. The investigation shows how detailed and accurate models could be derived applying photogrammetric processing software, simply by using images of the community, without visiting the site.
NLTE line formation of Fe for late-type stars. I. Standard stars with 1D and <3D> model atmospheres
Bergemann, Maria; Collet, Remo; Magic, Zazralt; Asplund, Martin
2012-01-01
We investigate departures from LTE in the line formation of Fe for a number of well-studied late-type stars in different evolutionary stages. A new model of Fe atom was constructed from the most up-to-date theoretical and experimental atomic data available so far. Non-local thermodynamic equilibrium (NLTE) line formation calculations for Fe were performed using 1D hydrostatic MARCS and MAFAGS-OS model atmospheres, as well as the spatial and temporal average stratifications from full 3D hydrodynamical simulations of stellar convection computed using the Stagger code. It is shown that the Fe I/Fe II ionization balance can be well established with the 1D and mean 3D models under NLTE including calibrated inelastic collisions with H I calculated from the Drawin's (1969) formulae. Strong low-excitation Fe I lines are very sensitive to the atmospheric structure; classical 1D models fail to provide consistent excitation balance, particularly so for cool metal-poor stars. A better agreement between Fe I lines spannin...
3D modelling for multipurpose cadastre
Abduhl Rahman, A.; Van Oosterom, P.J.M.; Hua, T.C.; Sharkawi, K.H.; Duncan, E.E.; Azri, N.; Hassan, M.I.
2012-01-01
Three-dimensional (3D) modelling of cadastral objects (such as legal spaces around buildings, around utility networks and other spaces) is one of the important aspects for a multipurpose cadastre (MPC). This paper describes the 3D modelling of the objects for MPC and its usage to the knowledge of 3D
Wittkowski, M; Freytag, B; Scholz, M; Hoefner, S; Karovicova, I; Whitelock, P A
2016-01-01
We obtained a total of 20 near-infrared K-band spectro-interferometric snapshot observations of the Mira variables o Cet, R Leo, R Aqr, X Hya, W Vel, and R Cnc with a spectral resolution of about 1500. We compared observed flux and visibility spectra with predictions by CODEX 1D dynamic model atmospheres and with azimuthally averaged intensities based on CO5BOLD 3D dynamic model atmospheres including convection. Our visibility data confirm the presence of spatially extended molecular atmospheres located above the continuum radii with large-scale inhomogeneities or clumps that contribute a few percent of the total flux. The detailed structure of the inhomogeneities or clumps show a variability on time scales of 3 months and above. Both modeling attempts provided satisfactory fits to our data. In particular, they are both consistent with the observed decrease in the visibility function at molecular bands of water vapor and CO, indicating a spatially extended molecular atmosphere. Observational variability phase...
J.-D. Paris
2010-07-01
Full Text Available We evaluate the GEOS-Chem atmospheric transport model (v8-02-01 of CO2 over 2003–2006, driven by GEOS-4 and GEOS-5 meteorology from the NASA Goddard Global Modelling and Assimilation Office, using surface, aircraft and space-borne concentration measurements of CO2. We use an established ensemble Kalman filter to estimate a posteriori biospheric+biomass burning (BS+BB and oceanic (OC CO2 fluxes from 22 geographical regions, following the TransCom 3 protocol, using boundary layer CO2 data from a subset of GLOBALVIEW surface sites. Global annual net BS+BB+OC CO2 fluxes over 2004–2006 for GEOS-4 (GEOS-5 meteorology are −4.4±0.9 (−4.2±0.9, −3.9±0.9 (−4.5±0.9, and −5.2±0.9 (−4.9±0.9 Pg C yr−1 , respectively. The regional a posteriori fluxes are broadly consistent in the sign and magnitude of the TransCom-3 study for 1992–1996, but we find larger net sinks over northern and southern continents. We find large departures from our a priori over Europe during summer 2003, over temperate Eurasia during 2004, and over North America during 2005, reflecting an incomplete description of terrestrial carbon dynamics. We find GEOS-4 (GEOS-5 a posteriori CO2 concentrations reproduce the observed surface trend of 1.91–2.43 ppm yr−1, depending on latitude, within 0.15 ppm yr−1 (0.2 ppm yr−1 and the seasonal cycle within 0.2 ppm (0.2 ppm at all latitudes. We find the a posteriori model reproduces the aircraft vertical profile measurements of CO2 over North America and Siberia generally within 1.5 ppm in the free and upper troposphere but can be biased by up to 4–5 ppm in the boundary layer at the start and end of the growing season. The model has a small negative bias in the free troposphere CO2 trend (1.95–2.19 ppm yr−1 compared to AIRS data which has a trend of 2.21–2.63 ppm yr−1 during 2004–2006, consistent with surface data. Model CO2 concentrations in the upper troposphere, evaluated using CONTRAIL (Comprehensive
Sibylle Dueri
2010-03-01
Full Text Available A 3D hydrodynamic and contaminant fate model was implemented for polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs in Thau lagoon. The hydrodynamic model was tested against temperature and salinity measurements, while the contaminant fate model was assessed against available data collected at different stations inside the lagoon. The model results allow an assessment of the spatial and temporal variability of the distribution of contaminants in the lagoon, the seasonality of loads and the role of atmospheric deposition for the input of PCDD/Fs. The outcome suggests that air is an important source of PCDD/Fs for this ecosystem, therefore the monitoring of air pollution is very appropriate for assessing the inputs of these contaminants. These results call for the development of integrated environmental protection policies.
Face Detection with a 3D Model
Barbu, Adrian; Lay, Nathan; Gramajo, Gary
2014-01-01
This paper presents a part-based face detection approach where the spatial relationship between the face parts is represented by a hidden 3D model with six parameters. The computational complexity of the search in the six dimensional pose space is addressed by proposing meaningful 3D pose candidates by image-based regression from detected face keypoint locations. The 3D pose candidates are evaluated using a parameter sensitive classifier based on difference features relative to the 3D pose. A...
National Aeronautics and Space Administration — Aura observes the chemical content of the atmosphere to track the state of the ozone layer and the dispersion of airborne pollution. Polygons: 6 Vertices: 4
National Aeronautics and Space Administration — Aqua carries six state-of-the-art instruments to observe the Earth's oceans, atmosphere, land, ice and snow covers, and vegetation, providing high measurement...
National Aeronautics and Space Administration — The Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation (CALIPSO) satellite provides new insight into the role that clouds and atmospheric aerosols...
FROM 3D MODEL DATA TO SEMANTICS
My Abdellah Kassimi
2012-01-01
Full Text Available The semantic-based 3D models retrieval systems have become necessary since the increase of 3D modelsdatabases. In this paper, we propose a new method for the mapping problem between 3D model data andsemantic data involved in semantic based retrieval for 3D models given by polygonal meshes. First, wefocused on extracting invariant descriptors from the 3D models and analyzing them to efficient semanticannotation and to improve the retrieval accuracy. Selected shape descriptors provide a set of termscommonly used to describe visually a set of objects using linguistic terms and are used as semanticconcept to label 3D model. Second, spatial relationship representing directional, topological anddistance relationships are used to derive other high-level semantic features and to avoid the problem ofautomatic 3D model annotation. Based on the resulting semantic annotation and spatial concepts, anontology for 3D model retrieval is constructed and other concepts can be inferred. This ontology is usedto find similar 3D models for a given query model. We adopted the query by semantic example approach,in which the annotation is performed mostly automatically. The proposed method is implemented in our3D search engine (SB3DMR, tested using the Princeton Shape Benchmark Database.
Gallagher, A J; Bonifacio, P; Ludwig, H -G; Steffen, M; Spite, M
2016-01-01
Recent developments in the three-dimensional (3D) spectral synthesis code Linfor3D have meant that, for the first time, large spectral wavelength regions, such as molecular bands, can be synthesised with it in a short amount of time. A detailed spectral analysis of the synthetic G-band for several dwarf turn-off-type 3D atmospheres (5850 <= T_eff [K] <= 6550, 4.0 <= log g <= 4.5, -3.0 <= [Fe/H] <= -1.0) was conducted, under the assumption of local thermodynamic equilibrium. We also examine carbon and oxygen molecule formation at various metallicity regimes and discuss the impact it has on the G-band. Using a qualitative approach, we describe the different behaviours between the 3D atmospheres and the traditional one-dimensional (1D) atmospheres and how the different physics involved inevitably leads to abundance corrections, which differ over varying metallicities. Spectra computed in 1D were fit to every 3D spectrum to determine the 3D abundance correction. Early analysis revealed that the ...
Holmgren, Steen; Rüdiger, Bjarne; Tournay, Bruno
2001-01-01
We have worked with the construction and use of 3D city models for about ten years. This work has given us valuable experience concerning model methodology. In addition to this collection of knowledge, our perception of the concept of city models has changed radically. In order to explain...... of 3D city models....
Spatial data modelling for 3D GIS
Abdul-Rahman, Alias
2007-01-01
This book covers fundamental aspects of spatial data modelling specifically on the aspect of three-dimensional (3D) modelling and structuring. Realisation of ""true"" 3D GIS spatial system needs a lot of effort, and the process is taking place in various research centres and universities in some countries. The development of spatial data modelling for 3D objects is the focus of this book.
3D Simulations of methane convective storms on Titan's atmosphere
Hueso, R.; Sánchez-Lavega, A.
2005-08-01
The arrival of the Cassini/Huygens mission to Titan has opened an unprecedented opportunity to study the atmosphere of this satellite. Under the pressure-temperature conditions on Titan, methane, a large atmospheric component amounting perhaps to a 3-5% of the atmosphere, is close to its triple point, potentially playing a similar role as water on Earth. The Huygens probe has shown a terrain shaped by erosion of probably liquid origin, suggestive of past rain. On the other hand, Voyager IRIS spectroscopic observations of Titan imply a saturated atmosphere of methane (amounting perhaps to 150 covered by methane clouds, if we think on Earth meteorology. However, observations from Earth and Cassini have shown that clouds are localized, transient and fast evolving, in particular in the South Pole (currently in its summer season). This might imply a lack of widespread presence on Titan of nuclei where methane could initiate condensation and particle growth with subsequent precipitation. We investigate different scenarios of moist convective storms on Titan using a complete 3D atmospheric model that incorporates a full microphysics treatment required to study cloud formation processes under a saturated atmosphere with low concentration of condensation nuclei. We study local convective development under a variety of atmospheric conditions: sub-saturation, super-saturation, abundances of condensation nuclei fall, condensation nuclei lifted from the ground or gently falling from the stratosphere. We show that under the appropriate circumstances, precipitation rates comparable to typical tropical storms on Earth can be found. Acknowledgements: This work has been funded by Spanish MCYT PNAYA2003-03216, fondos FEDER and Grupos UPV 15946/2004. R. Hueso acknowledges a post-doc fellowship from Gobierno Vasco.
Compression of 3D models with NURBS
Santa Cruz Ducci, Diego; Ebrahimi, Touradj
2005-01-01
With recent progress in computing, algorithmics and telecommunications, 3D models are increasingly used in various multimedia applications. Examples include visualization, gaming, entertainment and virtual reality. In the multimedia domain 3D models have been traditionally represented as polygonal meshes. This piecewise planar representation can be thought of as the analogy of bitmap images for 3D surfaces. As bitmap images, they enjoy great flexibility and are particularly well suited to des...
3D modelling for multipurpose cadastre
Abduhl Rahman, A.; P. J. M. Van Oosterom; T. C. Hua; Sharkawi, K.H.; E. E. Duncan; Azri, N.; Hassan, M. I.
2012-01-01
Three-dimensional (3D) modelling of cadastral objects (such as legal spaces around buildings, around utility networks and other spaces) is one of the important aspects for a multipurpose cadastre (MPC). This paper describes the 3D modelling of the objects for MPC and its usage to the knowledge of 3D cadastre since more and more related agencies attempt to develop or embed 3D components into the MPC. We also intend to describe the initiative by Malaysian national mapping and cadastral agency (...
Curating Architectural 3D CAD Models
MacKenzie Smith
2009-06-01
Full Text Available Normal 0 Increasing demand to manage and preserve 3-dimensional models for a variety of physical phenomena (e.g., building and engineering designs, computer games, or scientific visualizations is creating new challenges for digital archives. Preserving 3D models requires identifying technical formats for the models that can be maintained over time, and the available formats offer different advantages and disadvantages depending on the intended future uses of the models. Additionally, the metadata required to manage 3D models is not yet standardized, and getting intellectual proposal rights for digital models is uncharted territory. The FACADE Project at MIT is investigating these challenges in the architecture, engineering and construction (AEC industry and has developed recommendations and systems to support digital archives in dealing with digital 3D models and related data. These results can also be generalized to other domains doing 3D modeling.
Computer Modelling of 3D Geological Surface
Kodge, B G
2011-01-01
The geological surveying presently uses methods and tools for the computer modeling of 3D-structures of the geographical subsurface and geotechnical characterization as well as the application of geoinformation systems for management and analysis of spatial data, and their cartographic presentation. The objectives of this paper are to present a 3D geological surface model of Latur district in Maharashtra state of India. This study is undertaken through the several processes which are discussed in this paper to generate and visualize the automated 3D geological surface model of a projected area.
3-D Human Modeling and Animation
Ratner, Peter
2012-01-01
3-D Human Modeling and Animation Third Edition All the tools and techniques you need to bring human figures to 3-D life Thanks to today's remarkable technology, artists can create and animate realistic, three-dimensional human figures that were not possible just a few years ago. This easy-to-follow book guides you through all the necessary steps to adapt your own artistic skill in figure drawing, painting, and sculpture to this exciting digital canvas. 3-D Human Modeling and Animation, Third Edition starts you off with simple modeling, then prepares you for more advanced techniques for crea
Computer Modelling of 3D Geological Surface
Kodge B. G.
2011-02-01
Full Text Available The geological surveying presently uses methods and tools for the computer modeling of 3D-structures of the geographical subsurface and geotechnical characterization as well as the application of geoinformation systems for management and analysis of spatial data, and their cartographic presentation. The objectives of this paper are to present a 3D geological surface model of Latur district in Maharashtra state of India. This study is undertaken through the several processes which are discussed in this paper to generate and visualize the automated 3D geological surface model of a projected area.
Multifractal modelling and 3D lacunarity analysis
This study presents a comparative evaluation of lacunarity of 3D grey level models with different types of inhomogeneity. A new method based on the 'Relative Differential Box Counting' was developed to estimate the lacunarity features of grey level volumes. To validate our method, we generated a set of 3D grey level multifractal models with random, anisotropic and hierarchical properties. Our method gives a lacunarity measurement correlated with the theoretical one and allows a better model classification compared with a classical approach.
A polarized atmospheric radiative transfer model for the computation of radiative transfer inside three-dimensional inhomogeneous mediums is described. This code is based on Monte Carlo methods and takes into account the polarization state of the light. Specificities introduced by such consideration are presented. After validation of the model by comparisons with adding-doubling computations, examples of reflectances simulated from a synthetic inhomogeneous cirrus cloud are analyzed and compared with reflectances obtained with the classical assumption of a plane parallel homogeneous cloud (1D approximation). As polarized reflectance is known to saturate for optical thickness of about 3, one could think that they should be less sensitive to 3D effects than total reflectances. However, at high spatial resolution (80 m), values of polarized reflectances much higher than the ones predicted by the 1D theory can be reached. The study of the reflectances of a step cloud shows that these large values are the results of illumination and shadowing effects similar to those often observed on total reflectances. In addition, we show that for larger spatial resolution (10 km), the so-called plane-parallel bias leads to a non-negligible overestimation of the polarized reflectances of about 7-8%.
3D face modeling, analysis and recognition
Daoudi, Mohamed; Veltkamp, Remco
2013-01-01
3D Face Modeling, Analysis and Recognition presents methodologies for analyzing shapes of facial surfaces, develops computational tools for analyzing 3D face data, and illustrates them using state-of-the-art applications. The methodologies chosen are based on efficient representations, metrics, comparisons, and classifications of features that are especially relevant in the context of 3D measurements of human faces. These frameworks have a long-term utility in face analysis, taking into account the anticipated improvements in data collection, data storage, processing speeds, and application s
Automatic balancing of 3D models
Christiansen, Asger Nyman; Schmidt, Ryan; Bærentzen, Jakob Andreas
2014-01-01
3D printing technologies allow for more diverse shapes than are possible with molds and the cost of making just one single object is negligible compared to traditional production methods. However, not all shapes are suitable for 3D print. One of the remaining costs is therefore human time spent......, in these cases, we will apply a rotation of the object which only deforms the shape a little near the base. No user input is required but it is possible to specify manufacturing constraints related to specific 3D print technologies. Several models have successfully been balanced and printed using both polyjet...
Creating a 3D Game Character Model
Paasikivi, Joni
2014-01-01
This thesis goes through the process of modeling a low poly 3D model for a video game project from the perspective of a novice 3D artist. The goal was to prepare a stylized low polygon model of less than 6000 triangles, based on pre-made design and a living person. The program used in this project was 3Ds Max. The process starts with the creation of the reference images for the 3Ds Max and goes through the process of modeling the wireframe model, unwrapping the model for texturizing, and crea...
Measuring Visual Closeness of 3-D Models
Morales, Jose A.
2012-09-01
Measuring visual closeness of 3-D models is an important issue for different problems and there is still no standardized metric or algorithm to do it. The normal of a surface plays a vital role in the shading of a 3-D object. Motivated by this, we developed two applications to measure visualcloseness, introducing normal difference as a parameter in a weighted metric in Metro’s sampling approach to obtain the maximum and mean distance between 3-D models using 3-D and 6-D correspondence search structures. A visual closeness metric should provide accurate information on what the human observers would perceive as visually close objects. We performed a validation study with a group of people to evaluate the correlation of our metrics with subjective perception. The results were positive since the metrics predicted the subjective rankings more accurately than the Hausdorff distance.
Multifractal modelling and 3D lacunarity analysis
Hanen, Akkari, E-mail: bettaieb.hanen@topnet.t [Laboratoire de biophysique, TIM, Faculte de Medecine (Tunisia); Imen, Bhouri, E-mail: bhouri_imen@yahoo.f [Unite de recherche ondelettes et multifractals, Faculte des sciences (Tunisia); Asma, Ben Abdallah, E-mail: asma.babdallah@cristal.rnu.t [Laboratoire de biophysique, TIM, Faculte de Medecine (Tunisia); Patrick, Dubois, E-mail: pdubois@chru-lille.f [INSERM, U 703, Lille (France); Hedi, Bedoui Mohamed, E-mail: medhedi.bedoui@fmm.rnu.t [Laboratoire de biophysique, TIM, Faculte de Medecine (Tunisia)
2009-09-28
This study presents a comparative evaluation of lacunarity of 3D grey level models with different types of inhomogeneity. A new method based on the 'Relative Differential Box Counting' was developed to estimate the lacunarity features of grey level volumes. To validate our method, we generated a set of 3D grey level multifractal models with random, anisotropic and hierarchical properties. Our method gives a lacunarity measurement correlated with the theoretical one and allows a better model classification compared with a classical approach.
3D Modeling Engine Representation Summary Report
Steven Prescott; Ramprasad Sampath; Curtis Smith; Timothy Yang
2014-09-01
Computers have been used for 3D modeling and simulation, but only recently have computational resources been able to give realistic results in a reasonable time frame for large complex models. This summary report addressed the methods, techniques, and resources used to develop a 3D modeling engine to represent risk analysis simulation for advanced small modular reactor structures and components. The simulations done for this evaluation were focused on external events, specifically tsunami floods, for a hypothetical nuclear power facility on a coastline.
3D gender recognition using cognitive modeling
Fagertun, Jens; Andersen, Tobias; Hansen, Thomas;
2013-01-01
We use 3D scans of human faces and cognitive modeling to estimate the “gender strength”. The “gender strength” is a continuous class variable of the gender, superseding the traditional binary class labeling. To visualize some of the visual trends humans use when performing gender classification, we...
3D gender recognition using cognitive modeling
Fagertun, Jens; Andersen, Tobias; Hansen, Thomas; Paulsen, Rasmus Reinhold
2013-01-01
We use 3D scans of human faces and cognitive modeling to estimate the “gender strength”. The “gender strength” is a continuous class variable of the gender, superseding the traditional binary class labeling. To visualize some of the visual trends humans use when performing gender classification, ...
3D object-oriented image analysis in 3D geophysical modelling
Fadel, I.; van der Meijde, M.; Kerle, N.;
2015-01-01
Non-uniqueness of satellite gravity interpretation has traditionally been reduced by using a priori information from seismic tomography models. This reduction in the non-uniqueness has been based on velocity-density conversion formulas or user interpretation of the 3D subsurface structures (objects......) based on the seismic tomography models and then forward modelling these objects. However, this form of object-based approach has been done without a standardized methodology on how to extract the subsurface structures from the 3D models. In this research, a 3D object-oriented image analysis (3D OOA......) approach was implemented to extract the 3D subsurface structures from geophysical data. The approach was applied on a 3D shear wave seismic tomography model of the central part of the East African Rift System. Subsequently, the extracted 3D objects from the tomography model were reconstructed in the 3D...
Debris Dispersion Model Using Java 3D
Thirumalainambi, Rajkumar; Bardina, Jorge
2004-01-01
This paper describes web based simulation of Shuttle launch operations and debris dispersion. Java 3D graphics provides geometric and visual content with suitable mathematical model and behaviors of Shuttle launch. Because the model is so heterogeneous and interrelated with various factors, 3D graphics combined with physical models provides mechanisms to understand the complexity of launch and range operations. The main focus in the modeling and simulation covers orbital dynamics and range safety. Range safety areas include destruct limit lines, telemetry and tracking and population risk near range. If there is an explosion of Shuttle during launch, debris dispersion is explained. The shuttle launch and range operations in this paper are discussed based on the operations from Kennedy Space Center, Florida, USA.
Illustrating the disassembly of 3D models
Guo, Jianwei
2013-10-01
We present a framework for the automatic disassembly of 3D man-made models and the illustration of the disassembly process. Given an assembled 3D model, we first analyze the individual parts using sharp edge loops and extract the contact faces between each pair of neighboring parts. The contact faces are then used to compute the possible moving directions of each part. We then present a simple algorithm for clustering the sets of the individual parts into meaningful sub-assemblies, which can be used for a hierarchical decomposition. We take the stability of sub-assemblies into account during the decomposition process by considering the upright orientation of the input models. Our framework also provides a user-friendly interface to enable the superimposition of the constraints for the decomposition. Finally, we visualize the disassembly process by generating an animated sequence. The experiments demonstrate that our framework works well for a variety of complex models. © 2013 Elsevier Ltd.
Integrated Biogeomorphological Modeling Using Delft3D
Ye, Q.; Jagers, B.
2011-12-01
The skill of numerical morphological models has improved significantly from the early 2D uniform, total load sediment models (with steady state or infrequent wave updates) to recent 3D hydrodynamic models with multiple suspended and bed load sediment fractions and bed stratigraphy (online coupled with waves). Although there remain many open questions within this combined field of hydro- and morphodynamics, we observe an increasing need to include biological processes in the overall dynamics. In riverine and inter-tidal environments, there is often an important influence by riparian vegetation and macrobenthos. Over the past decade more and more researchers have started to extend the simulation environment with wrapper scripts and other quick code hacks to estimate their influence on morphological development in coastal, estuarine and riverine environments. Although one can in this way quickly analyze different approaches, these research tools have generally not been designed with reuse, performance and portability in mind. We have now implemented a reusable, flexible, and efficient two-way link between the Delft3D open source framework for hydrodynamics, waves and morphology, and the water quality and ecology modules. The same link will be used for 1D, 2D and 3D modeling on networks and both structured and unstructured grids. We will describe the concepts of the overall system, and illustrate it with some first results.
Adaptive Enhancement of 3D Scenes using Hierarchical Registration of Texture-Mapped 3D Models
Ramalingam, Srikumar; Lodha, Suresh
2003-01-01
Adaptive fusion of new information in a 3D urban scene is an important goal to achieve in computer vision, graphics, and visualization. In this work we acquire new image pairs of a scene from closer distances and extract 3D models of successively higher resolutions. We present a new hierarchical approach to register these texture-mapped 3D models with a coarse 3D texture mapped model of an urban scene. First, we use the standard reconstruction algorithm to construct 3D models after establishi...
Sensing and compressing 3-D models
Krumm, J. [Sandia National Labs., Albuquerque, NM (United States). Intelligent System Sensors and Controls Dept.
1998-02-01
The goal of this research project was to create a passive and robust computer vision system for producing 3-D computer models of arbitrary scenes. Although the authors were unsuccessful in achieving the overall goal, several components of this research have shown significant potential. Of particular interest is the application of parametric eigenspace methods for planar pose measurement of partially occluded objects in gray-level images. The techniques presented provide a simple, accurate, and robust solution to the planar pose measurement problem. In addition, the representational efficiency of eigenspace methods used with gray-level features were successfully extended to binary features, which are less sensitive to illumination changes. The results of this research are presented in two papers that were written during the course of this project. The papers are included in sections 2 and 3. The first section of this report summarizes the 3-D modeling efforts.
GENERATING 3D MODEL FROM VIDEO
Svetlana Mijakovska
2014-12-01
Full Text Available In this paper the process of 3D modelling from video is presented. Analysed previous research related to this process, and specifically described algorithms for detecting and matching key points. We described their advantages and disadvantages, and made a critical analysis of algorithms. In this paper, the three detectors (SUSAN, Plessey and Förstner are tested and compare. We used video taken with hand held camera of a cube and compare these detectors on it (taking into account their parameters of accuracy and repeatability. In conclusion, we practically made 3D model of the cube from video used these detectors in the first step of the process and three algorithms (RANSAC, MSAC and MLESAC for matching data.
Berchtold, Waldemar; Schäfer, Marcel; Rettig, Michael; Steinebach, Martin
2014-02-01
3D models and applications are of utmost interest in both science and industry. With the increment of their usage, their number and thereby the challenge to correctly identify them increases. Content identification is commonly done by cryptographic hashes. However, they fail as a solution in application scenarios such as computer aided design (CAD), scientific visualization or video games, because even the smallest alteration of the 3D model, e.g. conversion or compression operations, massively changes the cryptographic hash as well. Therefore, this work presents a robust hashing algorithm for 3D mesh data. The algorithm applies several different bit extraction methods. They are built to resist desired alterations of the model as well as malicious attacks intending to prevent correct allocation. The different bit extraction methods are tested against each other and, as far as possible, the hashing algorithm is compared to the state of the art. The parameters tested are robustness, security and runtime performance as well as False Acceptance Rate (FAR) and False Rejection Rate (FRR), also the probability calculation of hash collision is included. The introduced hashing algorithm is kept adaptive e.g. in hash length, to serve as a proper tool for all applications in practice.
3D modeling of buildings outstanding sites
Héno, Rapha?le
2014-01-01
Conventional topographic databases, obtained by capture on aerial or spatial images provide a simplified 3D modeling of our urban environment, answering the needs of numerous applications (development, risk prevention, mobility management, etc.). However, when we have to represent and analyze more complex sites (monuments, civil engineering works, archeological sites, etc.), these models no longer suffice and other acquisition and processing means have to be implemented. This book focuses on the study of adapted lifting means for "notable buildings". The methods tackled in this book cover las
Alfredsson, Jonas
2008-01-01
This report describes the work and the results found when comparing three different 3d modeler applications. The programs are 3ds Max, Maya and Cinema 4D. The comparisons focus on the possibilities/the amount of freedom these programs interface offer to its plugins. The comparisons are made from the point of view of a tool for creating animations developed as a plugin for these modelers. This plugins demands on the system it is loaded into have been analyzed and from the results of this analy...
The dual gonihedric 3D Ising model
Johnston, D A [Department of Mathematics, Heriot-Watt University, Riccarton, Edinburgh EH14 4AS (United Kingdom); Ranasinghe, R P K C M, E-mail: D.A.Johnston@hw.ac.uk [Department of Mathematics, University of Sri Jayewardenepura, Gangodawila (Sri Lanka)
2011-07-22
We investigate the dual of the {kappa} = 0 gonihedric Ising model on a 3D cubic lattice, which may be written as an anisotropically coupled Ashkin-Teller model. The original {kappa} = 0 gonihedric model has a purely plaquette interaction, displays a first order transition and possesses a highly degenerate ground state. We find that the dual model admits a similar large ground state degeneracy as a result of the anisotropic couplings and investigate the coupled mean-field equations for the model on a single cube. We also carry out Monte Carlo simulations which confirm a first order phase transition in the model and suggest that the ground state degeneracy persists throughout the low temperature phase. Some exploratory cooling simulations also hint at non-trivial dynamical behaviour.
The dual gonihedric 3D Ising model
We investigate the dual of the κ = 0 gonihedric Ising model on a 3D cubic lattice, which may be written as an anisotropically coupled Ashkin-Teller model. The original κ = 0 gonihedric model has a purely plaquette interaction, displays a first order transition and possesses a highly degenerate ground state. We find that the dual model admits a similar large ground state degeneracy as a result of the anisotropic couplings and investigate the coupled mean-field equations for the model on a single cube. We also carry out Monte Carlo simulations which confirm a first order phase transition in the model and suggest that the ground state degeneracy persists throughout the low temperature phase. Some exploratory cooling simulations also hint at non-trivial dynamical behaviour.
3D Model of Surfactant Replacement Therapy
Grotberg, James; Tai, Cheng-Feng; Filoche, Marcel
2015-11-01
Surfactant Replacement Therapy (SRT) involves instillation of a liquid-surfactant mixture directly into the lung airway tree. Though successful in neonatal applications, its use in adults had early success followed by failure. We present the first mathematical model of 3D SRT where a liquid plug propagates through the tree from forced inspiration. In two separate modeling steps, the plug first deposits a coating film on the airway wall which subtracts from its volume, a ``coating cost''. Then the plug splits unevenly at the airway bifurcation due to gravity. The steps are repeated until a plug ruptures or reaches the tree endpoint alveoli/acinus. The model generates 3D images of the resulting acinar distribution and calculates two global indexes, efficiency and homogeneity. Simulating published literature, the earlier successful adult SRT studies show comparatively good index values, while the later failed studies do not. Those unsuccessful studies used smaller dose volumes with higher concentration mixtures, apparently assuming a well mixed compartment. The model shows that adult lungs are not well mixed in SRT due to the coating cost and gravity effects. Returning to the higher dose volume protocols could save many thousands of lives annually in the US. Supported by NIH Grants HL85156, HL84370 and Agence Nationale de la Recherche, ANR no. 2010-BLAN-1119-05.
Design and Implementation of 3D Model Database for General-Purpose 3D GIS
XU Weiping; ZHU Qing; DU Zhiqiang; ZHANG Yeting
2010-01-01
To improve the reusability of three-dimensional (3D) models and simplify the complexity of natural scene reconstruction, this paper presents a 3D model database for universal 3D GIS. After the introduction of its extensible function architecture,accompanied by the conclusion of implicit spatial-temporal hierarchy of models in any reconstructed scene of 3D GIS for general purpose, several key issues are discussed in detail, such as the storage and management of 3D models and related retrieval and load method, as well as the interfaces for further on-demand development. Finally, the validity and feasibility of this model database are proved through its application in the development of 3D visualization system of railway operation.
Dong, C.; Bougher, S. W.; Ma, Y.; Toth, G.; Lee, Y.; Nagy, A. F.; Tenishev, V.; Pawlowski, D. J.; Meng, X.; Combi, M. R.
2013-12-01
The study of the solar wind interaction with Mars upper atmosphere/ionosphere has triggered a great of interest in recent years. Among the large number of topics in this research area, the investigation of ion escape fluxes has become increasingly important due to its potential impact on the long-term evolution of Mars atmosphere (e.g., loss of water) over its history. In the present work, we adopt the 3-D Mars cold neutral atmosphere profiles (0~300 km) from the newly developed and validated Mars Global Ionosphere Thermosphere Model (M-GITM) and the 3-D hot oxygen profiles (100km~5RM) from the exosphere Monte Carlo model Adaptive Mesh Particle Simulator (AMPS). We apply these 3-D model outputs fields into the 3-D BATS-R-US Mars multi-fluid MHD model (100km~20RM) that can better simulate the interplay between Mars upper atmosphere and solar wind by considering the dynamics of individual ion species. The multi-fluid model solves separate continuity, momentum and energy equations for each ion species (H+, O+, O2+, CO2+). The M-GITM model together with the AMPS exosphere model take into account the effects of solar cycle and seasonal variations on both cold and hot neutral atmospheres, allowing us to investigate the corresponding effects on the Mars upper atmosphere ion escape by using a one-way coupling approach, i.e., both the M-GITM and AMPS model outputs are used as the inputs for the multi-fluid model and M-GITM is used as input into the AMPS exosphere model. The calculations are carried out for selected cases with different nominal solar wind, solar cycle and crustal field orientation conditions. This work has the potential to provide predictions of ion escape rates for comparison to future data to be returned by the MAVEN primary mission (2014-2016) and thereby improve our understanding of present day escape processes. Acknowledgments: The work presented here was supported by NASA grants NNH10CC04C, NNX09AL26G, NSF grant ATM-0535811.
3D Model Assisted Image Segmentation
Jayawardena, Srimal; Hutter, Marcus
2012-01-01
The problem of segmenting a given image into coherent regions is important in Computer Vision and many industrial applications require segmenting a known object into its components. Examples include identifying individual parts of a component for process control work in a manufacturing plant and identifying parts of a car from a photo for automatic damage detection. Unfortunately most of an object's parts of interest in such applications share the same pixel characteristics, having similar colour and texture. This makes segmenting the object into its components a non-trivial task for conventional image segmentation algorithms. In this paper, we propose a "Model Assisted Segmentation" method to tackle this problem. A 3D model of the object is registered over the given image by optimising a novel gradient based loss function. This registration obtains the full 3D pose from an image of the object. The image can have an arbitrary view of the object and is not limited to a particular set of views. The segmentation...
Using 3D Scanning in 3D Character Modeling and Game Figure Production
guo, Jun
2008-01-01
The theme of this thesis was to discuss the theory of 3D scanning, focus on the flowchart of using 3D NextEngine Desktop Scanner hardware and software as well as the 3D game character exporting and importing in both 3ds Max and CryENGINE2 Sandbox2. The purpose of this final-year project was to scan models made of modeling paste using the 3D NextEngine ScanStudio. The models were developed and imported as raw files into 3dsMax. At the same step, the skeletons were adjusted an...
MC3D modelling of stratified explosion
It is known that a steam explosion can occur in a stratified geometry and that the observed yields are lower than in the case of explosion in a premixture configuration. However, very few models are available to quantify the amount of melt which can be involved and the pressure peak that can be developed. In the stratified application of the MC3D code, mixing and fragmentation of the melt are explained by the growth of Kelvin Helmholtz instabilities due to the shear flow of the two phase coolant above the melt. Such a model is then used to recalculate the Frost-Ciccarelli tin-water experiment. Pressure peak, speed of propagation, bubble shape and erosion height are well reproduced as well as the influence of the inertial constraint (height of the water pool). (author)
Regional geothermal 3D modelling in Denmark
Poulsen, S. E.; Balling, N.; Bording, T. S.; Nielsen, S. B.
2012-04-01
In the pursuit of sustainable and low carbon emission energy sources, increased global attention has been given to the exploration and exploitation of geothermal resources within recent decades. In 2009 a national multi-disciplinary geothermal research project was established. As a significant part of this project, 3D temperature modelling is to be carried out, with special emphasis on temperatures of potential geothermal reservoirs in the Danish area. The Danish subsurface encompasses low enthalpy geothermal reservoirs of mainly Triassic and Jurassic age. Geothermal plants at Amager (Copenhagen) and Thisted (Northern Jutland) have the capacity of supplying the district heating network with up to 14 MW and 7 MW, respectively, by withdrawing warm pore water from the Gassum (Lower Jurassic/Upper Triassic) and Bunter (Lower Triassic) sandstone reservoirs, respectively. Explorative studies of the subsurface temperature regime typically are based on a combination of observations and modelling. In this study, the open-source groundwater modelling code MODFLOW is modified to simulate the subsurface temperature distribution in three dimensions by taking advantage of the mathematical similarity between saturated groundwater flow (Darcy flow) and heat conduction. A numerical model of the subsurface geology in Denmark is built and parameterized from lithological information derived from joint interpretation of seismic surveys and borehole information. Boundary conditions are constructed from knowledge about the heat flow from the Earth's interior and the shallow ground temperature. Matrix thermal conductivities have been estimated from analysis of high-resolution temperature logs measured in deep wells and porosity-depth relations are included using interpreted main lithologies. The model takes into account the dependency of temperature and pressure on thermal conductivity. Moreover, a transient model based correction of the paleoclimatic thermal disturbance caused by the
A compressor model has been implemented in the RELAP5-3D code. The model is similar to that of the existing pump model, and performs the same function on a gas as the pump performs on a single-phase or two-phase fluid. The compressor component consists of an inlet junction and a control volume, and optionally, an outlet junction. This feature permits cascading compressor components in series. The equations describing the physics of the compressor are derived from first principles. These equations are used to obtain the head, the torque, and the energy dissipation. Compressor performance is specified using a map, specific to the design of the machine, in terms of the ratio of outlet-to-inlet total (or stagnation) pressure and adiabatic efficiency as functions of rotational velocity and flow rate. The input quantities are specified in terms of dimensionless variables, which are corrected to stagnation density and stagnation sound speed. A small correction was formulated for the input of efficiency to account for the error introduced by assumption of constant density when integrating the momentum equation. Comparison of the results of steady-state operation of the compressor model to those of the MIT design calculation showed excellent agreement for both pressure ratio and power
Bertrand, Tanguy; Forget, Francois
2016-04-01
To interpret New Horizons observations and simulate the Pluto climate system, we have developed a Global Climate Model (GCM) of Pluto's atmosphere. In addition to a 3D "dynamical core" which solves the equation of meteorology, the model takes into account the N2 condensation and sublimation and its thermal and dynamical effects, the vertical turbulent mixing, the radiative transfer through methane and carbon monoxide, molecular thermal conduction, and a detailed surface thermal model with different thermal inertia for various timescales (diurnal, seasonal). The GCM also includes a detailed model of the CH4 and CO cycles, taking into account their transport by the atmospheric circulation and turbulence, as well as their condensation and sublimation on the surface and in the atmosphere, possibly forming methane ice clouds. The GCM consistently predicts the 3D methane abundance in the atmosphere, which is used as an input for our radiative transfer calculation. In a second phase, we also developed a volatile transport model, derived from the GCM, which can be run over thousands of years in order to reach consistent initial states for the GCM runs and better explore the seasonal processes on Pluto. Results obtained with the volatile transport model show that the distribution of N2, CH4 and CO ices primarily depends on the seasonal thermal inertia used for the different ices, and is affected by the assumed topography as well. As observed, it is possible to form a large and permanent nitrogen glacier with CO and CH4 ice deposits in an equatorial basin corresponding to Sputnik Planum, while having a surface pressure evolution consistent with stellar occultations and New Horizons data. In addition, most of the methane ice is sequestered with N2 ice in the basin but seasonal polar caps of CH4 frosts also form explaining the bright polar caps observed with Hubble in the 1980s and in line with New Horizons observations. Using such balanced combination of surface and
3D Geological Modeling under Extremely Complex Geological Conditions
Yanlin Shao; Ailing Zheng; Youbin He; Keyan Xiao
2012-01-01
3D modeling method is divided into geospatial modeling and 3D geological modeling. 3D geological modeling technique has become a favorable tool for people to observe and analyze the geological body enriched in mineral resources. Unlike geospatial modeling, 3D geological modeling must consider various geological conditions affecting spatial shape and petrophysical distribution of geological body for its complexity. This article analyzes the uncertainty, complexity and diversity of geological b...
Forget, Francois; Bertrand, Tanguy; Vangvichith, Melanie; Leconte, Jeremy
2015-11-01
To interpret New Horizons observations and simulate the Pluto climate system, we have developed a Global Climate Model (GCM) of Pluto's atmosphere. In addition to a 3D "dynamical core" which solves the equations of meteorology, the model takes into account the N2 condensation and sublimation and its thermal and dynamical effects, the vertical turbulent mixing, the radiative transfer through methane and carbon monoxide, molecular thermal conduction, and a detailed surface thermal model with different thermal inertia for various timescales (diurnal, seasonal).The GCM also includes a detailed model of the CH4 and CO cycles, taking into account their transport by the atmospheric circulation and turbulence, as well as their condensation and sublimation on the surface and in the atmosphere, possibly forming methane ice clouds. The GCM consistently predicts the 3D methane abundance in the atmosphere, which is used as an input for our radiative transfer calculation.Because of the radiative timescales, the surface thermal inertia and the slow evolution of the methane cycle, the model takes more than 20 years to become insensitive to the assumed atmospheric initial states. We typically start our simulations in 1975 to simulate 2015, but remain sensitive to the assumed initial ices distribution and seasonal thermal inertia map. The simulated thermal structure and waves can be compared to the New Horizons occultations measurements. As observed, the longitudinal variability is very limited, for fundamental reasons.In addition, we have developed a 3D model of the formation of organic hazes within the GCM. It includes the different steps of aerosols formation as understood on Titan: photolysis of CH4 in the upper atmosphere by the Lyman-alpha radiation, production of various gaseous precursor species, conversion into solid particles through chemistry and aggregation processes, and gravitational sedimentation. Significant amount of haze particles are found to be present at all
3D Models of Stellar Interactions
Mohamed, S.; Podsiadlowski, Ph.; Booth, R.; Maercker, M.; Ramstedt, S.; Vlemmings, W.; Harries, T.; Mackey, J.; Langer, N.; Corradi, R.
2014-04-01
Symbiotic binaries consist of a cool, evolved mass-losing giant and an accreting compact companion. As symbiotic nebulae show similar morphologies to those in planetary nebulae (so much so that it is often difficult to distinguish between the two), they are ideal laboratories for understanding the role a binary companion plays in shaping the circumstellar envelopes in these evolved systems. We will present 3D Smoothed Particle Hydrodynamics (SPH) models of interacting binaries, e.g. R Aquarii and Mira, and discuss the formation of spiral outflows, arcs, shells and equatorial density enhancements.We will also discuss the implications of the former for planetary nebulae, e.g. the Egg Nebula and Cat's Eye, and the latter for the formation of bipolar geometries, e.g. M2-9. We also investigate accretion and angular momentum evolution in symbiotic binaries which may be important to understand the formation of jets and more episodic mass-loss features we see in circumstellar envelopes and the orbital characteristics of binary central stars of planetary nebulae.
Efficient 3D scene modeling and mosaicing
Nicosevici, Tudor
2013-01-01
This book proposes a complete pipeline for monocular (single camera) based 3D mapping of terrestrial and underwater environments. The aim is to provide a solution to large-scale scene modeling that is both accurate and efficient. To this end, we have developed a novel Structure from Motion algorithm that increases mapping accuracy by registering camera views directly with the maps. The camera registration uses a dual approach that adapts to the type of environment being mapped. In order to further increase the accuracy of the resulting maps, a new method is presented, allowing detection of images corresponding to the same scene region (crossovers). Crossovers then used in conjunction with global alignment methods in order to highly reduce estimation errors, especially when mapping large areas. Our method is based on Visual Bag of Words paradigm (BoW), offering a more efficient and simpler solution by eliminating the training stage, generally required by state of the art BoW algorithms. Also, towards dev...
VIRTUAL 3D CITY MODELING: TECHNIQUES AND APPLICATIONS
S. P. Singh; K. Jain; V. R. Mandla
2013-01-01
3D city model is a digital representation of the Earth's surface and it's related objects such as Building, Tree, Vegetation, and some manmade feature belonging to urban area. There are various terms used for 3D city models such as "Cybertown", "Cybercity", "Virtual City", or "Digital City". 3D city models are basically a computerized or digital model of a city contains the graphic representation of buildings and other objects in 2.5 or 3D. Generally three main Geomatics approach ...
Building 3D models with modo 701
García, Juan Jiménez
2013-01-01
The book will focus on creating a sample application throughout the book, building gradually from chapter to chapter.If you are new to the 3D world, this is the key to getting started with a modern software in the modern visualization industry. Only minimal previous knowledge is needed.If you have some previous knowledge about 3D content creation, you will find useful tricks that will differentiate the learning experience from a typical user manual from this, a practical guide concerning the most common problems and situations and how to solve them.
B. Aouizerats
2010-10-01
Full Text Available Obtaining a good description of aerosol optical properties for a physically and chemically complex evolving aerosol is computationally very expensive at present. The goal of this work is to propose a new numerical module computing the optical properties for complex aerosol particles at low numerical cost so that it can be implemented in atmospheric models. This method aims to compute the optical properties online as a function of a given complex refractive index deduced from the aerosol chemical composition and the size parameters corresponding to the particles.
The construction of look-up tables from the imaginary and the real part of the complex refractive index and size parameters will also be explained. This approach is validated for observations acquired during the EUCAARI (European integrated project on aerosol cloud climate air quality interactions campaign on the Cabauw tower during May 2008 and its computing cost is also estimated.
These comparisons show that the module manages to reproduce the scattering and absorbing behaviour of the aerosol during most of the fifteen-day period of observation with a very cheap computationally cost.
3D fast wavelet network model-assisted 3D face recognition
Said, Salwa; Jemai, Olfa; Zaied, Mourad; Ben Amar, Chokri
2015-12-01
In last years, the emergence of 3D shape in face recognition is due to its robustness to pose and illumination changes. These attractive benefits are not all the challenges to achieve satisfactory recognition rate. Other challenges such as facial expressions and computing time of matching algorithms remain to be explored. In this context, we propose our 3D face recognition approach using 3D wavelet networks. Our approach contains two stages: learning stage and recognition stage. For the training we propose a novel algorithm based on 3D fast wavelet transform. From 3D coordinates of the face (x,y,z), we proceed to voxelization to get a 3D volume which will be decomposed by 3D fast wavelet transform and modeled after that with a wavelet network, then their associated weights are considered as vector features to represent each training face . For the recognition stage, an unknown identity face is projected on all the training WN to obtain a new vector features after every projection. A similarity score is computed between the old and the obtained vector features. To show the efficiency of our approach, experimental results were performed on all the FRGC v.2 benchmark.
Using Insight3D to produce a 3D building model
Natlačen, Daša
2015-01-01
The leadership in object 3D modeling was in the past decade taken over by integration of close range photogrammetry and computer vision. Major progress was achieved in the development of software tools, which enable obtaining spatial data from series of images taken from different perspectives. In order to gain new experience, Insight3D application was chosen to be addressed in this master’s thesis out of the rich set of software tools available on the market. The main goal of ...
3D Modeling Techniques for Print and Digital Media
Stephens, Megan Ashley
In developing my thesis, I looked to gain skills using ZBrush to create 3D models, 3D scanning, and 3D printing. The models created compared the hearts of several vertebrates and were intended for students attending Comparative Vertebrate Anatomy. I used several resources to create a model of the human heart and was able to work from life while creating heart models from other vertebrates. I successfully learned ZBrush and 3D scanning, and successfully printed 3D heart models. ZBrush allowed me to create several intricate models for use in both animation and print media. The 3D scanning technique did not fit my needs for the project, but may be of use for later projects. I was able to 3D print using two different techniques as well.
Planning for brachytherapy using a 3D-simulation model
A 3D-simulation model made with a milling system was applied to HDR-brachytherapy. The 3D-simulation model is used to simulate the 3D-structure of the lesion and the surrounding organs before the actual catheterization for brachytherapy. The first case was recurrent prostatic cancer in a 61-year-old man. The other case was lymph node recurrence of a 71-year-old woman's upper gum cancer. In both cases, the 3D-simulation model was very useful to simulate the 3D-conformation, to plan the treatment process and to avoid the risk accompanying treatment. (author)
3D PIC Modeling of Microcavity Discharge
Hopkins, Matthew; Manginell, Ronald; Moore, Christopher; Yee, Benjamin; Moorman, Matthew
2015-09-01
We present a number of techniques and challenges in simulating the transient behavior of a microcavity discharge. Our microcavities are typically cylindrical with diameters approximately 50 - 100 μm, heights of 50 - 200 μm, pressure near atmospheric, and operate at a few hundred volts. We employ a fully kinetic simulation methodology, the Particle-in-Cell (PIC) method, with interparticle collisions handled via methods based on direct simulation Monte Carlo (DSMC). In particular, we explicitly include kinetic electrons. Some of the challenges we encounter include variations in number densities, external circuit coupling, and time step resolution constraints. By employing dynamic particle weighting (particle weights vary over time by species and location) we can mitigate some of the challenges modeling systems with 107 variations in number densities. Smoothing mechanisms have been used to attempt to mitigate external circuit response. We perform our simulations on hundreds or thousands of processing cores to accommodate the computational work inherent in using relatively small time step sizes (e.g., 50 fs for a 100 ns calculation). In addition, particle weighting issues inherent to three-dimensional low temperature plasma systems will be mentioned. Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy's NNSA under Contract DE-AC04-94AL85000.
Integrating 3D modeling, photogrammetry and design
Foster, Shaun
2014-01-01
This book looks at the convergent nature of technology and its relationship to the field of photogrammetry and 3D design. This is a facet of a broader discussion of the nature of technology itself and the relationship of technology to art, as well as an examination of the educational process. In the field of technology-influenced design-based education it is natural to push for advanced technology, yet within a larger institution the constraints of budget and adherence to tradition must be accepted. These opposing forces create a natural balance; in some cases constraints lead to greater creat
3D modeling of metallic grain growth
George, D.; Carlson, N.; Gammel, J.T.; Kuprat, A.
1999-06-01
This paper will describe simulating metallic grain growth using the Gradient Weighted Moving Finite Elements code, GRAIN3D. The authors also describe the set of mesh topology change operations developed to respond to changes in the physical topology such as the collapse of grains and to maintain uniform calculational mesh quality. Validation of the method is demonstrated by comparison to analytic calculations. The authors present results of multigrain simulations where grain boundaries evolve by mean curvature motion and include results which incorporate grain boundary orientation dependence.
National Aeronautics and Space Administration — Jason 1 is an oceanography mission to monitor global ocean circulation, study the ties between the oceans and atmosphere, improve global climate forecasts and...
National Aeronautics and Space Administration — Launched in April 2006, CloudSat monitors the state of the Earth’s atmosphere and weather with a sophisticated radar system. The instrument, jointly developed with...
APPLICATION OF 3D MODELING IN 3D PRINTING FOR THE LOWER JAW RECONSTRUCTION
Yu. Yu. Dikov
2015-01-01
Full Text Available Aim of study: improvement of functional and aesthetic results of microsurgery reconstructions of the lower jaw due to the use of the methodology of 3D modeling and 3D printing. Application of this methodology has been demonstrated on the example of treatment of 4 patients with locally distributed tumors of the mouth cavity, who underwent excision of the tumor with simultaneous reconstruction of the lower jaw with revascularized fibular graft.Before, one patient has already undergo segmental resection of the lower jaw with the defect replacement with the avascular ileac graft and a reconstruction plate. Then, a relapse of the disease and lysis of the graft has developed with him. Modeling of the graft according to the shape of the lower jaw was performed by making osteotomies of the bone part of the graft using three-dimensional virtual models created by computed tomography data. Then these 3D models were printed with a 3D printer of plastic with the scale of 1:1 with the fused deposition modeling (FDM technology and were used during the surgery in the course of modeling of the graft. Sterilizing of the plastic model was performed in the formalin chamber.This methodology allowed more specific reconstruction of the resected fragment of the lower jaw and get better functional and aesthetic results and prepare patients to further dental rehabilitation. Advantages of this methodology are the possibility of simultaneous performance of stages of reconstruction and resection and shortening of the time of surgery.
PERFORMANCE EVALUATION OF 3D MODELING SOFTWARE FOR UAV PHOTOGRAMMETRY
Yanagi, H; H. Chikatsu
2016-01-01
UAV (Unmanned Aerial Vehicle) photogrammetry, which combines UAV and freely available internet-based 3D modeling software, is widely used as a low-cost and user-friendly photogrammetry technique in the fields such as remote sensing and geosciences. In UAV photogrammetry, only the platform used in conventional aerial photogrammetry is changed. Consequently, 3D modeling software contributes significantly to its expansion. However, the algorithms of the 3D modelling software are black box algori...
OCTG Premium Threaded Connection 3D Parametric Finite Element Model
Ahsan, Nabeel
2016-01-01
Full 360 degree 3D finite element models are the most complete representation of Oil Country Tubular Goods (OCTG) premium threaded connections. Full 3D models can represent helical threads and boundary conditions required to simulate make-up and service loading. A methodology is developed to create a 360 degree full 3D parametric finite element model with helical threads as an effective design and analysis tool. The approach is demonstrated with the creation of a metal-to-metal seal integral ...
Summary on Several Key Techniques in 3D Geological Modeling
Gang Mei
2014-01-01
Several key techniques in 3D geological modeling including planar mesh generation, spatial interpolation, and surface intersection are summarized in this paper. Note that these techniques are generic and widely used in various applications but play a key role in 3D geological modeling. There are two essential procedures in 3D geological modeling: the first is the simulation of geological interfaces using geometric surfaces and the second is the building of geological objects by means of vario...
Statistical Model of the 3-D Braided Composites Strength
XIAO Laiyuan; ZUO Weiwei; CAI Ganwei; LIAO Daoxun
2007-01-01
Based on the statistical model for the tensile statistical strength of unidirectional composite materials and the stress analysis of 3-D braided composites, a new method is proposed to calculate the tensile statistical strength of the 3-D braided composites. With this method, the strength of 3-D braided composites can be calculated with very large accuracy, and the statistical parameters of 3-D braided composites can be determined. The numerical result shows that the tensile statistical strength of 3-D braided composites can be predicted using this method.
Life in 3D is never flat: 3D models to optimise drug delivery.
Fitzgerald, Kathleen A; Malhotra, Meenakshi; Curtin, Caroline M; O' Brien, Fergal J; O' Driscoll, Caitriona M
2015-10-10
The development of safe, effective and patient-acceptable drug products is an expensive and lengthy process and the risk of failure at different stages of the development life-cycle is high. Improved biopharmaceutical tools which are robust, easy to use and accurately predict the in vivo response are urgently required to help address these issues. In this review the advantages and challenges of in vitro 3D versus 2D cell culture models will be discussed in terms of evaluating new drug products at the pre-clinical development stage. Examples of models with a 3D architecture including scaffolds, cell-derived matrices, multicellular spheroids and biochips will be described. The ability to simulate the microenvironment of tumours and vital organs including the liver, kidney, heart and intestine which have major impact on drug absorption, distribution, metabolism and toxicity will be evaluated. Examples of the application of 3D models including a role in formulation development, pharmacokinetic profiling and toxicity testing will be critically assessed. Although utilisation of 3D cell culture models in the field of drug delivery is still in its infancy, the area is attracting high levels of interest and is likely to become a significant in vitro tool to assist in drug product development thus reducing the requirement for unnecessary animal studies. PMID:26220617
3D Hilbert Space Filling Curves in 3D City Modeling for Faster Spatial Queries
Ujang, Uznir; Antón Castro, Francesc/François; Azri, Suhaibah;
2014-01-01
The advantages of three dimensional (3D) city models can be seen in various applications including photogrammetry, urban and regional planning, computer games, etc. They expand the visualization and analysis capabilities of Geographic Information Systems on cities, and they can be developed using...
Automatic Generation of 3D Building Models for Sustainable Development
Sugihara, Kenichi
2015-01-01
3D city models are important in urban planning for sustainable development. Urban planners draw maps for efficient land use and a compact city. 3D city models based on these maps are quite effective in understanding what, if this alternative plan is realized, the image of a sustainable city will be. However, enormous time and labour has to be consumed to create these 3D models, using 3D modelling software such as 3ds Max or SketchUp. In order to automate the laborious steps, a GIS and CG inte...
Importing a 3D model from an industrial design
Tran Thi, Thien
2015-01-01
In the media industry, sharing and transferring a 3D model to other programs for different stages of design is widely used. The final year project was carried out based on a case study in which a 3D model was imported from an industrial design to Autodesk 3ds Max. The thesis focuses on defining the workflow for importing a third-party 3D model to the 3ds Max program. In general, importing a 3D model made by one program to another one always presents many challenges. The purposes of this s...
3D scene modeling from multiple range views
Sequeira, Vitor; Goncalves, Joao G. M.; Ribeiro, M. Isabel
1995-09-01
This paper presents a new 3D scene analysis system that automatically reconstructs the 3D geometric model of real-world scenes from multiple range images acquired by a laser range finder on board of a mobile robot. The reconstruction is achieved through an integrated procedure including range data acquisition, geometrical feature extraction, registration, and integration of multiple views. Different descriptions of the final 3D scene model are obtained: a polygonal triangular mesh, a surface description in terms of planar and biquadratics surfaces, and a 3D boundary representation. Relevant experimental results from the complete 3D scene modeling are presented. Direct applications of this technique include 3D reconstruction and/or update of architectual or industrial plans into a CAD model, design verification of buildings, navigation of autonomous robots, and input to virtual reality systems.
Späth, Florian; Behrendt, Andreas; Muppa, Shravan Kumar; Metzendorf, Simon; Riede, Andrea; Wulfmeyer, Volker
2016-01-01
High-resolution three-dimensional (3-D) water vapor data of the atmospheric boundary layer (ABL) are required to improve our understanding of land–atmosphere exchange processes. For this purpose, the scanning differential absorption lidar (DIAL) of the University of Hohenheim (UHOH) was developed as well as new analysis tools and visualization methods. The instrument determines 3-D fields of the atmospheric water vapor number density with a temporal resolution of a few secon...
Visualization of 3D Geological Models on Google Earth
Choi, Y.; Um, J.; Park, M.
2013-05-01
Google Earth combines satellite imagery, aerial photography, thematic maps and various data sets to make a three-dimensional (3D) interactive image of the world. Currently, Google Earth is a popular visualization tool in a variety of fields and plays an increasingly important role not only for private users in daily life, but also for scientists, practitioners, policymakers and stakeholders in research and application. In this study, a method to visualize 3D geological models on Google Earth is presented. COLLAborative Design Activity (COLLADA, an open standard XML schema for establishing interactive 3D applications) was used to represent different 3D geological models such as borehole, fence section, surface-based 3D volume and 3D grid by triangle meshes (a set of triangles connected by their common edges or corners). In addition, we designed Keyhole Markup Language (KML, the XML-based scripting language of Google Earth) codes to import the COLLADA files into the 3D render window of Google Earth. The method was applied to the Grosmont formation in Alberta, Canada. The application showed that the combination of COLLADA and KML enables Google Earth to effectively visualize 3D geological structures and properties.; Visualization of the (a) boreholes, (b) fence sections, (c) 3D volume model and (d) 3D grid model of Grossmont formation on Google Earth
IVIS-3D: A tool for interactive 3D-visualisation of gravity models
Klesper, C.
EDV-based interactive visualisation methods have become a very essential part in the modelling and analysing of three-dimensional models in geoscience. The value of enhanced 3D-visualization for the process of modelling and validation of complex models increases with the number of capabilities to change independently display parameters and to combine different data, like model and process information. But this value also falls with increasing information and methods which slow down user interaction and confuses the user with too much information and the complexity of user interfaces (Houlding, 1994). Especially for interactive 3D-visualization and validation of geometric models, existing modelling systems can meet the user requirements only inadequate. So lacks of functionality are often compensated by the user with a patchwork of different programs. Now the task was to find or create new visualisation methods, to combine the capabilities of interactive 3D-visualization with an intuitive environment and to adapt these features to the existing gravity and magnetic modelling program IGMAS (Götze et al., 1988); (Schmidt, 1996).
a Fast Method for Measuring the Similarity Between 3d Model and 3d Point Cloud
Zhang, Zongliang; Li, Jonathan; Li, Xin; Lin, Yangbin; Zhang, Shanxin; Wang, Cheng
2016-06-01
This paper proposes a fast method for measuring the partial Similarity between 3D Model and 3D point Cloud (SimMC). It is crucial to measure SimMC for many point cloud-related applications such as 3D object retrieval and inverse procedural modelling. In our proposed method, the surface area of model and the Distance from Model to point Cloud (DistMC) are exploited as measurements to calculate SimMC. Here, DistMC is defined as the weighted distance of the distances between points sampled from model and point cloud. Similarly, Distance from point Cloud to Model (DistCM) is defined as the average distance of the distances between points in point cloud and model. In order to reduce huge computational burdens brought by calculation of DistCM in some traditional methods, we define SimMC as the ratio of weighted surface area of model to DistMC. Compared to those traditional SimMC measuring methods that are only able to measure global similarity, our method is capable of measuring partial similarity by employing distance-weighted strategy. Moreover, our method is able to be faster than other partial similarity assessment methods. We demonstrate the superiority of our method both on synthetic data and laser scanning data.
A 3D Geometry Model Search Engine to Support Learning
Tam, Gary K. L.; Lau, Rynson W. H.; Zhao, Jianmin
2009-01-01
Due to the popularity of 3D graphics in animation and games, usage of 3D geometry deformable models increases dramatically. Despite their growing importance, these models are difficult and time consuming to build. A distance learning system for the construction of these models could greatly facilitate students to learn and practice at different…
The interplay of sunlight with clouds is a ubiquitous and often pleasant visual experience, but it conjures up major challenges for weather, climate, environmental science and beyond. Those engaged in the characterization of clouds (and the clear air nearby) by remote sensing methods are even more confronted. The problem comes, on the one hand, from the spatial complexity of real clouds and, on the other hand, from the dominance of multiple scattering in the radiation transport. The former ingredient contrasts sharply with the still popular representation of clouds as homogeneous plane-parallel slabs for the purposes of radiative transfer computations. In typical cloud scenes the opposite asymptotic transport regimes of diffusion and ballistic propagation coexist. We survey the three-dimensional (3D) atmospheric radiative transfer literature over the past 50 years and identify three concurrent and intertwining thrusts: first, how to assess the damage (bias) caused by 3D effects in the operational 1D radiative transfer models? Second, how to mitigate this damage? Finally, can we exploit 3D radiative transfer phenomena to innovate observation methods and technologies? We quickly realize that the smallest scale resolved computationally or observationally may be artificial but is nonetheless a key quantity that separates the 3D radiative transfer solutions into two broad and complementary classes: stochastic and deterministic. Both approaches draw on classic and contemporary statistical, mathematical and computational physics.
From 2D to 3D: Using Illumination Cones to Build 3d Face Model
To solve the problem derivate by lighting condition and position of the camera, a new method using illumination cones to build 3d face model has been proposed. Due to illumination variability, the same object can show dramatic difference even as being viewed in fixed pose. To handle this variability, an object recognition system must employ a representation that is either invariant to, or can model this variability. The proposed technique presents an appearance-based method for modeling the variability due to illumination in the images of objects. The method differs from past appearance-based methods. Evenmore, a small set of training images is used to generate a representation that the illumination cone models the complete set of images of an object with Lambertian reflectance surface under a combination of arbitrary point light sources at infinity. After building up the illumination cones, researches focus on how to present the 3d model of the face. Combining illumination and texture feature to build up 3d model of the face make it easy solving the problem in recognition of face under different pose
From 2D to 3D: Using Illumination Cones to Build 3d Face Model
Xiao, S S; Jin, M [TianJin University, Collage of Precision Instrument and Opto-Ectronics Engineering (China)
2006-10-15
To solve the problem derivate by lighting condition and position of the camera, a new method using illumination cones to build 3d face model has been proposed. Due to illumination variability, the same object can show dramatic difference even as being viewed in fixed pose. To handle this variability, an object recognition system must employ a representation that is either invariant to, or can model this variability. The proposed technique presents an appearance-based method for modeling the variability due to illumination in the images of objects. The method differs from past appearance-based methods. Evenmore, a small set of training images is used to generate a representation that the illumination cone models the complete set of images of an object with Lambertian reflectance surface under a combination of arbitrary point light sources at infinity. After building up the illumination cones, researches focus on how to present the 3d model of the face. Combining illumination and texture feature to build up 3d model of the face make it easy solving the problem in recognition of face under different pose.
Numerical simulation of 3D flows in atmospheric boundary layer
Šimonek, Jiří; Kozel, K.; Jaňour, Zbyněk
Praha : Ústav termomechaniky AV ČR, v. v. i, 2012 - (Šimurda, D.; Kozel, K.), s. 93-96 ISBN 978-80-87012-40-6. [Topical Problems of Fluid Mechanics 2012 . Praha (CZ), 15.02. 2012 -17.02. 2012 ] R&D Projects: GA ČR GAP101/12/1271 Institutional research plan: CEZ:AV0Z20760514 Keywords : numerical solution * atmospheric boundary layer * Navier-Stokes equation s Subject RIV: DG - Athmosphere Sciences, Meteorology
Numerical 3-D Modelling of Overflows
Larsen, Torben; Nielsen, L.; Jensen, B.; Christensen, E. D.
2008-01-01
-dimensional so-called Volume of Fluid Models (VOF-models) based on the full Navier-Stokes equations (named NS3 and developed by DHI Water & Environment) As a general conclusion, the two numerical models show excellent results when compared with measurements. However, considerable errors occur when......The present study uses laboratory experiments to evaluate the reliability of two types of numerical models of sewers systems: - 1-dimensional model based on the extended Saint-Venant equation including the term for curvature of the water surface (the so-called Boussinesq approximation) - 2- and 3...
Værkanalyse med digitale 3D modeller
Villaume, René Domine; Ørstrup, Finn Rude
2006-01-01
Projektet afprøve muligheder for Værkanalyse af danske arkitekturværker med anvendelse af digitale 3D modeller. Arkitektstuderende har i en workshop udarbejdet en 3D model af Arkitekt Vilhelm Lauritzens bygning til Københavns Lufthavn fra 1939. Modellen er herefter videreudviklet og yderligere...
Octree-based Robust Watermarking for 3D Model
Su Cai
2011-02-01
Full Text Available Three robust blind watermarking methods of 3D models based on Octree are proposed in this paper: OTC-W, OTP-W and Zero-W. Primary Component Analysis and Octree partition are used on 3D meshes. A scrambled binary image for OTC-W and a scrambled RGB image for OTP-W are separately embedded adaptively into the single child nodes at the bottom level of Octree structure. The watermark can be extracted without the original image and 3D model. Those two methods have high embedding capacity for 3D meshes. Meanwhile, they are robust against geometric transformation (like translation, rotation, uniform scaling and vertex reordering attacks. For Zero-W, higher nodes of Octree are used to construct ‘Zero-watermark’, which can resist simplification, noise and remeshing attacks. All those three methods are fit for 3D point cloud data and arbitrary 3D meshes.Three robust blind watermarking methods of 3D models based on Octree are proposed in this paper: OTC-W, OTP-W and Zero-W. Primary Component Analysis and Octree partition are used on 3D meshes. A scrambled binary image for OTC-W and a scrambled RGB image for OTP-W are separately embedded adaptively into the single child nodes at the bottom level of Octree structure. The watermark can be extracted without the original image and 3D model. Those two methods have high embedding capacity for 3D meshes. Meanwhile, they are robust against geometric transformation (like translation, rotation, uniform scaling and vertex reordering attacks. For Zero-W, higher nodes of Octree are used to construct ‘Zero-watermark’, which can resist simplification, noise and remeshing attacks. All those three methods are fit for 3D point cloud data and arbitrary 3D meshes.
An Automated 3d Indoor Topological Navigation Network Modelling
Jamali, A.; Rahman, A. A.; Boguslawski, P.; Gold, C. M.
2015-10-01
Indoor navigation is important for various applications such as disaster management and safety analysis. In the last decade, indoor environment has been a focus of wide research; that includes developing techniques for acquiring indoor data (e.g. Terrestrial laser scanning), 3D indoor modelling and 3D indoor navigation models. In this paper, an automated 3D topological indoor network generated from inaccurate 3D building models is proposed. In a normal scenario, 3D indoor navigation network derivation needs accurate 3D models with no errors (e.g. gap, intersect) and two cells (e.g. rooms, corridors) should touch each other to build their connections. The presented 3D modeling of indoor navigation network is based on surveying control points and it is less dependent on the 3D geometrical building model. For reducing time and cost of indoor building data acquisition process, Trimble LaserAce 1000 as surveying instrument is used. The modelling results were validated against an accurate geometry of indoor building environment which was acquired using Trimble M3 total station.
Highway 3D model from image and lidar data
Chen, Jinfeng; Chu, Henry; Sun, Xiaoduan
2014-05-01
We present a new method of highway 3-D model construction developed based on feature extraction in highway images and LIDAR data. We describe the processing road coordinate data that connect the image frames to the coordinates of the elevation data. Image processing methods are used to extract sky, road, and ground regions as well as significant objects (such as signs and building fronts) in the roadside for the 3D model. LIDAR data are interpolated and processed to extract the road lanes as well as other features such as trees, ditches, and elevated objects to form the 3D model. 3D geometry reasoning is used to match the image features to the 3D model. Results from successive frames are integrated to improve the final model.
EDGE REMOVAL OF 3D POLYGONAL MODEL USING MAYA API
SAMEER ARORA
2010-09-01
Full Text Available In various applications of computer graphics, 3D polygonal modeling is used, which consists millions of triangular polygon. In this polygon attributes – vertices, edges and faces’ details are to be stored. In order to control the processing time, storing space, and transfer speed, it is often required to reduce the information ofthese polygonal 3D models. In this paper an effort is made to reduce the number of edges. There are various methods to reduce faces and edges of these 3D models. A C++ dynamic link library as Maya Plugin has been created to remove number of edges of 3D triangular polygon model using the Quadric Error Metrics (QEM in MAYA v2010 x64 API. QEM allows fast and accurate geometric simplification of 3D models.
Several Strategies on 3D Modeling of Manmade Objects
SHAO Zhenfeng; LI Deren; CHENG Qimin
2004-01-01
Several different strategies of 3D modeling are adopted for different kinds of manmade objects. Firstly, for those manmade objects with regular structure, if 2D information is available and elevation information can be obtained conveniently, then 3D modeling of them can be executed directly. Secondly, for those manmade objects with complicated structure comparatively and related stereo images pair can be acquired, in the light of topology-based 3D model we finish 3D modeling of them by integrating automatic and semi-automatic object extraction. Thirdly, for the most complicated objects whose geometrical information cannot be got from stereo images pair completely, we turn to topological 3D model based on CAD.
An Automatic Registration Algorithm for 3D Maxillofacial Model
Qiu, Luwen; Zhou, Zhongwei; Guo, Jixiang; Lv, Jiancheng
2016-09-01
3D image registration aims at aligning two 3D data sets in a common coordinate system, which has been widely used in computer vision, pattern recognition and computer assisted surgery. One challenging problem in 3D registration is that point-wise correspondences between two point sets are often unknown apriori. In this work, we develop an automatic algorithm for 3D maxillofacial models registration including facial surface model and skull model. Our proposed registration algorithm can achieve a good alignment result between partial and whole maxillofacial model in spite of ambiguous matching, which has a potential application in the oral and maxillofacial reparative and reconstructive surgery. The proposed algorithm includes three steps: (1) 3D-SIFT features extraction and FPFH descriptors construction; (2) feature matching using SAC-IA; (3) coarse rigid alignment and refinement by ICP. Experiments on facial surfaces and mandible skull models demonstrate the efficiency and robustness of our algorithm.
<3D> NLTE line formation in the atmospheres of red supergiants
Bergemann, Maria; Davies, Ben; Plez, Bertrand; Gazak, Zach; Chiavassa, Andrea
2013-01-01
Red supergiants with their enormous brightness at J-band are ideal probes of cosmic chemical composition. It is therefore crucial to have realistic models of radiative transfer in their atmospheres, which will permit determination of abundances accurate to 0.15 dex, the precision attainable with future telescope facilities in galaxies as distant as tens of Mpc. Here, we study the effects of non-local thermodynamic equilibrium (NLTE) on the formation of iron, titanium, and silicon lines, which dominate J-band spectra of red supergiants. It is shown that the NLTE radiative transfer models enable accurate derivation of metallicity and effective temperature in the J-band. We also discuss consequences for RSG spectrum synthesis in different spectral windows, including the heavily TiO-blanketed optical region, and atmospheric structure. We then touch upon challenges of NLTE integration with new generation of 3D hydrodynamical RSG models and present the first calculations of NLTE spectra with the mean 3D model of Be...
NASA 3D Models: Cassini Assembly
National Aeronautics and Space Administration — Includes orbiter from CAD models. Accurate (to a fault) except no thermal blanketing is shown (this would cover most of the central structure of the spacecraft)....
A study of the 3D radiative transfer effect in cloudy atmospheres
Okata, M.; Teruyuki, N.; Suzuki, K.
2015-12-01
Evaluation of the effect of clouds in the atmosphere is a significant problem in the Earth's radiation budget study with their large uncertainties of microphysics and the optical properties. In this situation, we still need more investigations of 3D cloud radiative transer problems using not only models but also satellite observational data.For this purpose, we have developed a 3D-Monte-Carlo radiative transfer code that is implemented with various functions compatible with the OpenCLASTR R-Star radiation code for radiance and flux computation, i.e. forward and backward tracing routines, non-linear k-distribution parameterization (Sekiguchi and Nakajima, 2008) for broad band solar flux calculation, and DM-method for flux and TMS-method for upward radiance (Nakajima and Tnaka 1998). We also developed a Minimum cloud Information Deviation Profiling Method (MIDPM) as a method for a construction of 3D cloud field with MODIS/AQUA and CPR/CloudSat data. We then selected a best-matched radar reflectivity factor profile from the library for each of off-nadir pixels of MODIS where CPR profile is not available, by minimizing the deviation between library MODIS parameters and those at the pixel. In this study, we have used three cloud microphysical parameters as key parameters for the MIDPM, i.e. effective particle radius, cloud optical thickness and top of cloud temperature, and estimated 3D cloud radiation budget. We examined the discrepancies between satellite observed and mode-simulated radiances and three cloud microphysical parameter's pattern for studying the effects of cloud optical and microphysical properties on the radiation budget of the cloud-laden atmospheres.
A 3D Model Reconstruction Method Using Slice Images
LI Hong-an; KANG Bao-sheng
2013-01-01
Aiming at achieving the high accuracy 3D model from slice images, a new model reconstruction method using slice im-ages is proposed. Wanting to extract the outermost contours from slice images, the method of the improved GVF-Snake model with optimized force field and ray method is employed. And then, the 3D model is reconstructed by contour connection using the im-proved shortest diagonal method and judgment function of contour fracture. The results show that the accuracy of reconstruction 3D model is improved.
Virtual 3d City Modeling: Techniques and Applications
Singh, S. P.; Jain, K.; Mandla, V. R.
2013-08-01
3D city model is a digital representation of the Earth's surface and it's related objects such as Building, Tree, Vegetation, and some manmade feature belonging to urban area. There are various terms used for 3D city models such as "Cybertown", "Cybercity", "Virtual City", or "Digital City". 3D city models are basically a computerized or digital model of a city contains the graphic representation of buildings and other objects in 2.5 or 3D. Generally three main Geomatics approach are using for Virtual 3-D City models generation, in first approach, researcher are using Conventional techniques such as Vector Map data, DEM, Aerial images, second approach are based on High resolution satellite images with LASER scanning, In third method, many researcher are using Terrestrial images by using Close Range Photogrammetry with DSM & Texture mapping. We start this paper from the introduction of various Geomatics techniques for 3D City modeling. These techniques divided in to two main categories: one is based on Automation (Automatic, Semi-automatic and Manual methods), and another is Based on Data input techniques (one is Photogrammetry, another is Laser Techniques). After details study of this, finally in short, we are trying to give the conclusions of this study. In the last, we are trying to give the conclusions of this research paper and also giving a short view for justification and analysis, and present trend for 3D City modeling. This paper gives an overview about the Techniques related with "Generation of Virtual 3-D City models using Geomatics Techniques" and the Applications of Virtual 3D City models. Photogrammetry, (Close range, Aerial, Satellite), Lasergrammetry, GPS, or combination of these modern Geomatics techniques play a major role to create a virtual 3-D City model. Each and every techniques and method has some advantages and some drawbacks. Point cloud model is a modern trend for virtual 3-D city model. Photo-realistic, Scalable, Geo-referenced virtual 3
Micro- and macroturbulence predictions from CO5BOLD 3D stellar atmospheres
Steffen, M; Ludwig, H -G
2013-01-01
We present an overview of the current status of our efforts to derive the microturbulence and macroturbulence parameters (ximic and ximac) from the CIFIST grid of CO5BOLD 3D model atmospheres as a function of the basic stellar parameters Teff, log g, and [M/H]. The latest results for the Sun and Procyon show that the derived microturbulence parameter depends significantly on the numerical resolution of the underlying 3D simulation, confirming that `low-resolution' models tend to underestimate the true value of ximic. Extending the investigation to twelve further simulations with different Teff, log g, and [M/H], we obtain a first impression of the predicted trend of ximic over the Hertzsprung-Russell diagram: in agreement with empirical evidence, microturbulence increases towards higher effective temperature and lower gravity. The metallicity dependence of ximic must be interpreted with care, since it also reflects the deviation between the 1D and 3D photospheric temperature stratifications that increases sys...
Micro- and macroturbulence predictions from CO5BOLD 3D stellar atmospheres .
Steffen, M.; Caffau, E.; Ludwig, H.-G.
We present an overview of the current status of our efforts to derive the microturbulence and macroturbulence parameters (xi_mic and xi_mac) from the CIFIST grid of CO5BOLD 3D model atmospheres as a function of the basic stellar parameters T_{eff}, log g, and [M/H]. The latest results for the Sun and Procyon show that the derived microturbulence parameter depends significantly on the numerical resolution of the underlying 3D simulation, confirming that `low-resolution' models tend to underestimate the true value of xi_mic . Extending the investigation to 12 further simulations with different T_{eff}, log g, and [M/H], we obtain a first impression of the predicted trend of xi_mic over the Hertzsprung-Russell diagram: in agreement with empirical evidence, microturbulence increases towards higher effective temperature and lower gravity. The metallicity dependence of xi_mic must be interpreted with care, since it also reflects the deviation between the 1D and 3D photospheric temperature stratifications that increases systematically towards lower [M/H].
Image based 3D city modeling : Comparative study
Singh, S. P.; Jain, K.; Mandla, V. R.
2014-06-01
3D city model is a digital representation of the Earth's surface and it's related objects such as building, tree, vegetation, and some manmade feature belonging to urban area. The demand of 3D city modeling is increasing rapidly for various engineering and non-engineering applications. Generally four main image based approaches were used for virtual 3D city models generation. In first approach, researchers were used Sketch based modeling, second method is Procedural grammar based modeling, third approach is Close range photogrammetry based modeling and fourth approach is mainly based on Computer Vision techniques. SketchUp, CityEngine, Photomodeler and Agisoft Photoscan are the main softwares to represent these approaches respectively. These softwares have different approaches & methods suitable for image based 3D city modeling. Literature study shows that till date, there is no complete such type of comparative study available to create complete 3D city model by using images. This paper gives a comparative assessment of these four image based 3D modeling approaches. This comparative study is mainly based on data acquisition methods, data processing techniques and output 3D model products. For this research work, study area is the campus of civil engineering department, Indian Institute of Technology, Roorkee (India). This 3D campus acts as a prototype for city. This study also explains various governing parameters, factors and work experiences. This research work also gives a brief introduction, strengths and weakness of these four image based techniques. Some personal comment is also given as what can do or what can't do from these softwares. At the last, this study shows; it concluded that, each and every software has some advantages and limitations. Choice of software depends on user requirements of 3D project. For normal visualization project, SketchUp software is a good option. For 3D documentation record, Photomodeler gives good result. For Large city
Modelling Polymer Deformation during 3D Printing
McIlroy, Claire; Olmsted, Peter
Three-dimensional printing has the potential to transform manufacturing processes, yet improving the strength of printed parts, to equal that of traditionally-manufactured parts, remains an underlying issue. The fused deposition modelling technique involves melting a thermoplastic, followed by layer-by-layer extrusion to fabricate an object. The key to ensuring strength at the weld between layers is successful inter-diffusion. However, prior to welding, both the extrusion process and the cooling temperature profile can significantly deform the polymer micro-structure and, consequently, how well the polymers are able to ``re-entangle'' across the weld. In particular, polymer alignment in the flow can cause de-bonding of the layers and create defects. We have developed a simple model of the non-isothermal extrusion process to explore the effects that typical printing conditions and material rheology have on the conformation of a polymer melt. In particular, we incorporate both stretch and orientation using the Rolie-Poly constitutive equation to examine the melt structure as it flows through the nozzle, the subsequent alignment with the build plate and the resulting deformation due to the fixed nozzle height, which is typically less than the nozzle radius.
Technology for creating interactive 3D model printing equipment
Розенберг, О. А.; Хохлова, Розалія Анатоліївна
2013-01-01
The article analyzed the software to create interactive 3D models of printing equipment. The analysis revealed the advantages and disadvantages presented by the editors and determined the direction of research. The main parameters that influence the choice of software for interactive 3D simulation models, study models of production technologies in different applications are constructed classification software.The recommendations on the choice of the software to model, depending on the particu...
3D Model Retrieval Based on Semantic and Shape Indexes
Kassimi, My Abdellah
2011-01-01
The size of 3D models used on the web or stored in databases is becoming increasingly high. Then, an efficient method that allows users to find similar 3D objects for a given 3D model query has become necessary. Keywords and the geometry of a 3D model cannot meet the needs of users' retrieval because they do not include the semantic information. In this paper, a new method has been proposed to 3D models retrieval using semantic concepts combined with shape indexes. To obtain these concepts, we use the machine learning methods to label 3D models by k-means algorithm in measures and shape indexes space. Moreover, semantic concepts have been organized and represented by ontology language OWL and spatial relationships are used to disambiguate among models of similar appearance. The SPARQL query language has been used to question the information displayed in this language and to compute the similarity between two 3D models. We interpret our results using the Princeton Shape Benchmark Database and the results show ...
Hayek, W; Carlsson, M; Trampedach, R; Collet, R; Gudiksen, B V; Hansteen, V H; Leenaarts, J
2010-01-01
We present the implementation of a radiative transfer solver with coherent scattering in the new BIFROST code for radiative magneto-hydrodynamical (MHD) simulations of stellar surface convection. The code is fully parallelized using MPI domain decomposition, which allows for large grid sizes and improved resolution of hydrodynamical structures. We apply the code to simulate the surface granulation in a solar-type star, ignoring magnetic fields, and investigate the importance of coherent scattering for the atmospheric structure. A scattering term is added to the radiative transfer equation, requiring an iterative computation of the radiation field. We use a short-characteristics-based Gauss-Seidel acceleration scheme to compute radiative flux divergences for the energy equation. The effects of coherent scattering are tested by comparing the temperature stratification of three 3D time-dependent hydrodynamical atmosphere models of a solar-type star: without scattering, with continuum scattering only, and with bo...
Performance Analysis of a 3D Ionosphere Tomographic Model
Liu Zhi-zhao; Gao Yang
2003-01-01
A 3D high precision ionospheric model is developed based on tomography technique. This tomographic model employs GPS data observed by an operational network of dual-frequency GPS receivers. The methodology of developing a 3D ionospheric tomography model is briefly summarized. However emphasis is put on the analysis and evaluation of the accuracy variation of 3D ionosphere modeling with respect to the change of GPS data cutoff angle.Three typical cutoff angle values (15°, 20° and 25°) are tested. For each testing cutoff angle, the performances of the3D ionospheric model constructed using tomography technique are assessed by calibrating the model predicted ionospheric TEC with the GPS measured TEC and by employing the model predicted TEC to a practical GPS positioning application single point positioning (SPP).Test results indicate the 3D model predicted VTEC has about 0.4 TECU improvement in accuracy when cutoff angle rises from 15° to 20°. However, no apparent improvement is found from 20° to 25°. The model's improvement is also validated by the better SPP accuracy of 3D model than its counterpart-dual frequency model in the 20° and 25° cases.
Tangible 3D modeling of coherent and themed structures
Walther, Jeppe Ullè; Bærentzen, J. Andreas; Aanæs, Henrik
2016-01-01
We present CubeBuilder, a system for interactive, tangible 3D shape modeling. CubeBuilder allows the user to create a digital 3D model by placing physical, non-interlocking cubic blocks. These blocks may be placed in a completely arbitrary fashion and combined with other objects. In effect, this...... turns the task of 3D modeling into a playful activity that hardly requires any learning on the part of the user. The blocks are registered using a depth camera and entered into the cube graph where each block is a node and adjacent blocks are connected by edges. From the cube graph, we transform the...
The 3D model: explaining densification and deformation mechanisms by using 3D parameter plots.
Picker, Katharina M
2004-04-01
The aim of the study was to analyze very differently deforming materials using 3D parameter plots and consequently to gain deeper insights into the densification and deformation process described with the 3D model in order to define an ideal tableting excipient. The excipients used were dicalcium phosphate dihydrate (DCPD), sodium chloride (NaCl), microcrystalline cellulose (MCC), xylitol, mannitol, alpha-lactose monohydrate, maltose, hydroxypropyl methylcellulose (HPMC), sodium carboxymethylcellulose (NaCMC), cellulose acetate (CAC), maize starch, potato starch, pregelatinized starch, and maltodextrine. All of the materials were tableted to graded maximum relative densities (rhorel, max) using an eccentric tableting machine. The data which resulted, namely force, displacement, and time, were analyzed by the application of 3D modeling. Different particle size fractions of DCPD, CAC, and MCC were analyzed in addition. Brittle deforming materials such as DCPD exhibited a completely different 3D parameter plot, with low time plasticity, d, and low pressure plasticity, e, and a strong decrease in omega values when densification increased, in contrast to the plastically deforming MCC, which had much higher d, e, and omega values. e and omega values changed only slightly when densification increased for MCC. NaCl showed less of a decrease in omega values than DCPD did, and the d and e values were between those of MCC and DCPD. The sugar alcohols, xylitol and mannitol, behaved in a similar fashion to sodium chloride. This is also valid for the crystalline sugars, alpha-lactose monohydrate, and maltose. However, the sugars are more brittle than the sugar alcohols. The cellulose derivatives, HPMC, NaCMC, and CAC, are as plastic as MCC, however, their elasticity depends on substitution indicated by lower (more elastic) or higher (less elastic) omega values. The native starches, maize starch and potato starch, are very elastic, and pregelatinized starch and maltodextrine are
The 3-Dimensional Core Model DYN3D
Mittag, Siegfried; Rohde, Ulrich; Grundmann, Ulrich
2010-01-01
Analyzing the safety margins in transients and accidents of nuclear reactors 3-dimensional models of the core were used to avoid conservative assumptions needed for point kinetics or 1-dimensional models. Therefore the 3D code DYN3D has been developed for the analysis of reactivity initiated accidents (RIA) in thermal nuclear reactors. The power distributions are calculated with the help of nodal expansion methods (NEM) for hexagonal and Cartesian geometry. The fuel rod model and the thermohy...
Detailed Primitive-Based 3d Modeling of Architectural Elements
Remondino, F.; Lo Buglio, D.; Nony, N.; De Luca, L.
2012-07-01
The article describes a pipeline, based on image-data, for the 3D reconstruction of building façades or architectural elements and the successive modeling using geometric primitives. The approach overcome some existing problems in modeling architectural elements and deliver efficient-in-size reality-based textured 3D models useful for metric applications. For the 3D reconstruction, an opensource pipeline developed within the TAPENADE project is employed. In the successive modeling steps, the user manually selects an area containing an architectural element (capital, column, bas-relief, window tympanum, etc.) and then the procedure fits geometric primitives and computes disparity and displacement maps in order to tie visual and geometric information together in a light but detailed 3D model. Examples are reported and commented.
3-D network model and its parameter calibration
LIU; Xiaoyu(刘晓宇); LIANG; Naigang(梁乃刚); LI; Min(李敏)
2002-01-01
A material model, whose framework is parallel spring-bundles oriented in 3-D space, isproposed. Based on a discussion of the discrete schemes and optimum discretization of the solidangles, a 3-D network cell consisted of one-dimensional components is developed with its geomet-rical and physical parameters calibrated. It is proved that the 3-D network model is able to exactlysimulate materials with arbitrary Poisson ratio from 0 to 1/2, breaking through the limit that the pre-vious models in the literature are only suitable for materials with Poisson ratio from 0 to 1/3. A sim-plified model is also proposed to realize high computation accuracy within Iow computation cost.Examples demonstrate that the 3-D network model has particular superiority in the simulation ofshort-fiber reinforced composites.
3D Image Modelling and Specific Treatments in Orthodontics Domain
Dionysis Goularas
2007-01-01
Full Text Available In this article, we present a 3D specific dental plaster treatment system for orthodontics. From computer tomography scanner images, we propose first a 3D image modelling and reconstruction method of the Mandible and Maxillary based on an adaptive triangulation allowing management of contours meant for the complex topologies. Secondly, we present two specific treatment methods directly achieved on obtained 3D model allowing the automatic correction for the setting in occlusion of the Mandible and the Maxillary, and the teeth segmentation allowing more specific dental examinations. Finally, these specific treatments are presented via a client/server application with the aim of allowing a telediagnosis and treatment.
A method of 3D modeling and codec
QI Yue; YANG Shen; CAI Su; HOU Fei; SHEN XuKun; ZHAO QinPing
2009-01-01
3D modeling and codec of real objects are hot Issues in the field of virtual reality. In this paper, we propose an automatic registration two range Images method and a cycle based automatic global reg-istration algorithm for rapidly and automatically registering all range Images and constructing a real-istic 3D model. Besides, to meet the requirement of huge data transmission over Internet, we present a 3D mesh encoding/decoding method for encoding geometry, topology and attribute data with high compression ratio and supporting progressive transmission. The research results have already been applied successfully in digital museum.
Surface modelling in 3D city information system
Igor Petz
2009-10-01
Full Text Available Geographical information systems deal with terrain, cartographical and urban information; these systems allow gathering, maintaining and presentation of the included data. The approach of combininggeographical information systems with visualization methods of virtual reality is presented in this article. Virtual 3D City Information System is a project which purpose is to model parts of the city to 3D graphics using polygonal modelling for modelling objects by representing their surfaces using polygons. Realappearance is provided by using textures. Usually 3D exterior contains large data set of polygons. Presented system contains three parts: editor (modelling part, database and visualisation part. Thesystem is controlled by script (Python language using too. In conclusion are described some results of visualization of 3D scene that is represented as Košice city part.
Interactive 3D computer model of the human corneolimbal region
Molvaer, Rikke Kongshaug; Andreasen, Arne; Heegaard, Steffen;
2013-01-01
plan. In all, one low-magnification and 24 high-magnification interactive 3D models were created. Immunohistochemistry against stem cell markers p63 and ΔNp63α was performed as a supplement to the 3D models. RESULTS: Using the interactive 3D models, we identified three types of stem cell niches......PURPOSE: This study aims to clarify the existence of and to map the localization of different proposed stem cell niches in the corneal limbal region. MATERIALS AND METHODS: One human eye was cut into 2200 consecutive sections. Every other section was stained with haematoxylin and eosin, digitized...... in the superior limbal region and one LEC, six LCs and 12 FSPs in the inferior limbal region. Only few LECs, LCs and FSPs were localized nasally and temporally. CONCLUSION: Interactive 3D models are a powerful tool that may help to shed more light on the existence and spatial localization of the different stem...
Animation of 3D Model of Human Head
V. Michalcin
2007-04-01
Full Text Available The paper deals with the new algorithm of animation of 3D model of the human head in combination with its global motion. The designed algorithm is very fast and with low calculation requirements, because it does not need the synthesis of the input videosequence for estimation of the animation parameters as well as the parameters of global motion. The used 3D model Candide generates different expressions using its animation units which are controlled by the animation parameters. These ones are estimated on the basis of optical flow without the need of extracting of the feature points in the frames of the input videosequence because they are given by the selected vertices of the animation units of the calibrated 3D model Candide. The established multiple iterations inside the designed animation algorithm of 3D model of the human head between two successive frames significantly improved its accuracy above all for the large motion.
Formal representation of 3D structural geological models
Wang, Zhangang; Qu, Honggang; Wu, Zixing; Yang, Hongjun; Du, Qunle
2016-05-01
The development and widespread application of geological modeling methods has increased demands for the integration and sharing services of three dimensional (3D) geological data. However, theoretical research in the field of geological information sciences is limited despite the widespread use of Geographic Information Systems (GIS) in geology. In particular, fundamental research on the formal representations and standardized spatial descriptions of 3D structural models is required. This is necessary for accurate understanding and further applications of geological data in 3D space. In this paper, we propose a formal representation method for 3D structural models using the theory of point set topology, which produces a mathematical definition for the major types of geological objects. The spatial relationships between geologic boundaries, structures, and units are explained in detail using the 9-intersection model. Reasonable conditions for describing the topological space of 3D structural models are also provided. The results from this study can be used as potential support for the standardized representation and spatial quality evaluation of 3D structural models, as well as for specific needs related to model-based management, query, and analysis.
3D models for teaching and learning geosciences
Ward, Emma
2011-01-01
Although 3D geological models have been used in teaching as early as 1841, recent developments in 3D geological modelling methods and visualisation at the British Geological Survey (BGS) are providing unique resources for teaching and learning geoscience in the 21st century. Today’s geoscience students utilise a variety of cognitive processes and spatial skills during their learning experience. These include the application of schema’s, image construction, detecting patterns...
Numerical modelling of 3D woven preform deformations
Green, S D; Long, A.C.; El Said, B. S. F.; Hallett, S. R.
2014-01-01
In order to accurately predict the performance of 3D woven composites, it is necessary that realistic textile geometry is considered, since failure typically initiates at regions of high deformation or resin pockets. This paper presents the development of a finite element model based on the multi-chain digital element technique, as applied to simulate weaving and compaction of an orthogonal 3D woven composite. The model was reduced to the scale of the unit cell facilitating high fidelity resu...
Comparison of OpenFOAM and EllipSys3D for neutral atmospheric flow over complex terrain
Cavar, Dalibor; Réthoré, Pierre-Elouan; Bechmann, Andreas; Sørensen, Niels N.; Martinez, Benjamin, Jr; Zahle, Frederik; Berg, Jacob; Kelly, Mark C.
2016-01-01
The flow solvers OpenFOAM and EllipSys3D are compared in the case of neutral atmospheric flow over terrain using the test cases of Askervein and Bolund hills. Both solvers are run using the steady-state Reynolds-averaged Navier–Stokes k– turbulence model. One of the main modeling differences between the two solvers is the wall-function approach. The Open-FOAM v.1.7.1 uses a Nikuradse’s sand roughness model, while EllipSys3D uses a model based on the atmosphericroughness length. It is found th...
Performance Evaluation of 3d Modeling Software for Uav Photogrammetry
Yanagi, H.; Chikatsu, H.
2016-06-01
UAV (Unmanned Aerial Vehicle) photogrammetry, which combines UAV and freely available internet-based 3D modeling software, is widely used as a low-cost and user-friendly photogrammetry technique in the fields such as remote sensing and geosciences. In UAV photogrammetry, only the platform used in conventional aerial photogrammetry is changed. Consequently, 3D modeling software contributes significantly to its expansion. However, the algorithms of the 3D modelling software are black box algorithms. As a result, only a few studies have been able to evaluate their accuracy using 3D coordinate check points. With this motive, Smart3DCapture and Pix4Dmapper were downloaded from the Internet and commercial software PhotoScan was also employed; investigations were performed in this paper using check points and images obtained from UAV.
Automatic Texture Mapping of Architectural and Archaeological 3d Models
Kersten, T. P.; Stallmann, D.
2012-07-01
Today, detailed, complete and exact 3D models with photo-realistic textures are increasingly demanded for numerous applications in architecture and archaeology. Manual texture mapping of 3D models by digital photographs with software packages, such as Maxon Cinema 4D, Autodesk 3Ds Max or Maya, still requires a complex and time-consuming workflow. So, procedures for automatic texture mapping of 3D models are in demand. In this paper two automatic procedures are presented. The first procedure generates 3D surface models with textures by web services, while the second procedure textures already existing 3D models with the software tmapper. The program tmapper is based on the Multi Layer 3D image (ML3DImage) algorithm and developed in the programming language C++. The studies showing that the visibility analysis using the ML3DImage algorithm is not sufficient to obtain acceptable results of automatic texture mapping. To overcome the visibility problem the Point Cloud Painter algorithm in combination with the Z-buffer-procedure will be applied in the future.
Virtual Vixens 3D character modeling and scene placement
von Koenigsmarck, Arndt
2007-01-01
Features software workshops for 3ds Max, Maya, CINEMA 4D, Lightwave, and Softimage XSI.Hot, hotter, hottest. See how today''s leading modeling artists create 3D characters that sizzle and get the techniques you''ll need to create your own virtual vixens.Steven Stahlberg, Liam Kemp, Marco Patrito, and Sze Jones from Blur Studio are just a few of the 3D artists who share their secrets for making the fantasy females you wish were real. You''ll get their personal stories, insights into the profession, and new ways to conceive and construct your own 3D characters.Then, seven hands-on workshops demo
3-D numerical modelling of flow around a groin
Miller, R.; Roulund, A.; Sumer, B. Mutlu;
2003-01-01
A 3-D flow code, EllipSys3D, has been implemented to simulate the 3-D flow around a groin in steady current. The k turbulence model has been used for closure. Two kinds of groins are considered: (1) A vertical-wall groin, and (2) A groin with a side slope. Steady-flow simulations were conducted....... The paper reports early results of the investigation. The simulations capture main features of the flow around the groin. The horseshoe vortex in front of the vertical-wall groin is resolved. The vortex shedding at the head is not resolved because no transient flow simulations have been conducted at...
Validation of multipoint kinetics model against 3D Trikin Code
Validation of multipoint kinetics formulation for RELAP5 code has been carried out against 3D TRIKIN code. Core behavior of an asymmetric reactivity transient has been simulated through artificial tuning of lattice constants in 3D code. Individual node normalized reactivity has been conserved and power estimates from multipoint model have been compared with 3D simulation. It has been observed that localized peak power estimates from multipoint simulation are on higher side and therefore are conservative in nature. Improvements in multipoint formulation in regards to evolving coupling coefficients and involving more number of nodes can help in improving its accuracy to some extent. (author)
Gis-Based Smart Cartography Using 3d Modeling
Malinverni, E. S.; Tassetti, A. N.
2013-08-01
3D City Models have evolved to be important tools for urban decision processes and information systems, especially in planning, simulation, analysis, documentation and heritage management. On the other hand existing and in use numerical cartography is often not suitable to be used in GIS because not geometrically and topologically correctly structured. The research aim is to 3D structure and organize a numeric cartography for GIS and turn it into CityGML standardized features. The work is framed around a first phase of methodological analysis aimed to underline which existing standard (like ISO and OGC rules) can be used to improve the quality requirement of a cartographic structure. Subsequently, from this technical specifics, it has been investigated the translation in formal contents, using an owner interchange software (SketchUp), to support some guide lines implementations to generate a GIS3D structured in GML3. It has been therefore predisposed a test three-dimensional numerical cartography (scale 1:500, generated from range data captured by 3D laser scanner), tested on its quality according to the previous standard and edited when and where necessary. Cad files and shapefiles are converted into a final 3D model (Google SketchUp model) and then exported into a 3D city model (CityGML LoD1/LoD2). The GIS3D structure has been managed in a GIS environment to run further spatial analysis and energy performance estimate, not achievable in a 2D environment. In particular geometrical building parameters (footprint, volume etc.) are computed and building envelop thermal characteristics are derived from. Lastly, a simulation is carried out to deal with asbestos and home renovating charges and show how the built 3D city model can support municipal managers with risk diagnosis of the present situation and development of strategies for a sustainable redevelop.
WU Jian; CAO Dai-yong
2006-01-01
Sedimentary facies study is an important method in describing the property and distribution of reservoir. 3D geological modeling is a powerful tool in 3D characterization of geological bodies. By combining the sedimentary facies study with 3D geological modeling to generate 3D sedimentary facies model, the 3D geometry and distribution feature of sand bodies can be more accurately characterized, particularly in 3D view. In Liuchu oilfield of Jizhong depression, the Ed2IV formation was recognized as meandering river deposition facies and five sedimentary facies were identified, which include point bar sand, levee, channel margin, abandoned channel and floodplain. All the 24 sand body facies in Ed2IV were mapped and the 3D sedimentary facies model established based on 2D facies maps. The result shows that the 3D sedimentary facies model is well matched for the research result of sedimentary facies. Being an extension of traditional sedimentary study, the 3D sedimentary facies model can be used to describe the 3D geometry and distribution orders of a single sand body more reliably and more accurately.
Creating physical 3D stereolithograph models of brain and skull.
Daniel J Kelley
Full Text Available The human brain and skull are three dimensional (3D anatomical structures with complex surfaces. However, medical images are often two dimensional (2D and provide incomplete visualization of structural morphology. To overcome this loss in dimension, we developed and validated a freely available, semi-automated pathway to build 3D virtual reality (VR and hand-held, stereolithograph models. To evaluate whether surface visualization in 3D was more informative than in 2D, undergraduate students (n = 50 used the Gillespie scale to rate 3D VR and physical models of both a living patient-volunteer's brain and the skull of Phineas Gage, a historically famous railroad worker whose misfortune with a projectile tamping iron provided the first evidence of a structure-function relationship in brain. Using our processing pathway, we successfully fabricated human brain and skull replicas and validated that the stereolithograph model preserved the scale of the VR model. Based on the Gillespie ratings, students indicated that the biological utility and quality of visual information at the surface of VR and stereolithograph models were greater than the 2D images from which they were derived. The method we developed is useful to create VR and stereolithograph 3D models from medical images and can be used to model hard or soft tissue in living or preserved specimens. Compared to 2D images, VR and stereolithograph models provide an extra dimension that enhances both the quality of visual information and utility of surface visualization in neuroscience and medicine.
3D Bioprinting of Tissue/Organ Models.
Pati, Falguni; Gantelius, Jesper; Svahn, Helene Andersson
2016-04-01
In vitro tissue/organ models are useful platforms that can facilitate systematic, repetitive, and quantitative investigations of drugs/chemicals. The primary objective when developing tissue/organ models is to reproduce physiologically relevant functions that typically require complex culture systems. Bioprinting offers exciting prospects for constructing 3D tissue/organ models, as it enables the reproducible, automated production of complex living tissues. Bioprinted tissues/organs may prove useful for screening novel compounds or predicting toxicity, as the spatial and chemical complexity inherent to native tissues/organs can be recreated. In this Review, we highlight the importance of developing 3D in vitro tissue/organ models by 3D bioprinting techniques, characterization of these models for evaluating their resemblance to native tissue, and their application in the prioritization of lead candidates, toxicity testing, and as disease/tumor models. PMID:26895542
3D web visualization of huge CityGML models
Prandi, F.; Devigili, F.; Soave, M.; Di Staso, U.; De Amicis, R.
2015-08-01
Nowadays, rapid technological development into acquiring geo-spatial information; joined to the capabilities to process these data in a relative short period of time, allows the generation of detailed 3D textured city models that will become an essential part of the modern city information infrastructure (Spatial Data Infrastructure) and, can be used to integrate various data from different sources for public accessible visualisation and many other applications. One of the main bottlenecks, which at the moment limit the use of these datasets to few experts, is a lack on efficient visualization systems through the web and interoperable frameworks that allow standardising the access to the city models. The work presented in this paper tries to satisfy these two requirements developing a 3D web-based visualization system based on OGC standards and effective visualization concepts. The architectural framework, based on Services Oriented Architecture (SOA) concepts, provides the 3D city data to a web client designed to support the view process in a very effective way. The first part of the work is to design a framework compliant to the 3D Portrayal Service drafted by the of the Open Geospatial Consortium (OGC) 3D standardization working group. The latter is related to the development of an effective web client able to render in an efficient way the 3D city models.
3D MODEL OF TRANSFER OF POLLUTIONS FROM MOTOR VEHICLES TO THE AIR
Sukhinov, A.; Gadelshina, B.; Lyubomischenko, D.
2008-01-01
The article states the main ideas of mathematical simulation of pollution distribution from motor transport in the city atmosphere. Emission estimation model is based on solution of dual problems. A 3D model of advection-diffusion is shown. All models are paralleled on memory distribution system using domain decomposition method.
Arbitrary modeling of TSVs for 3D integrated circuits
Salah, Khaled; El-Rouby, Alaa
2014-01-01
This book presents a wide-band and technology independent, SPICE-compatible RLC model for through-silicon vias (TSVs) in 3D integrated circuits. This model accounts for a variety of effects, including skin effect, depletion capacitance and nearby contact effects. Readers will benefit from in-depth coverage of concepts and technology such as 3D integration, Macro modeling, dimensional analysis and compact modeling, as well as closed form equations for the through silicon via parasitics. Concepts covered are demonstrated by using TSVs in applications such as a spiral inductor?and inductive-based
3D Modelling of Biological Systems for Biomimetics
Shujun Zhang; Kevin Hapeshi; Ashok K. Bhattacharya
2004-01-01
With the advanced development of computer-based enabling technologies, many engineering, medical, biology,chemistry, physics and food science etc have developed to the unprecedented levels, which lead to many research and development interests in various multi-discipline areas. Among them, biomimetics is one of the most promising and attractive branches of study. Biomimetics is a branch of study that uses biological systems as a model to develop synthetic systems.To learn from nature, one of the fundamental issues is to understand the natural systems such animals, insects, plants and human beings etc. The geometrical characterization and representation of natural systems is an important fundamental work for biomimetics research. 3D modeling plays a key role in the geometrical characterization and representation, especially in computer graphical visualization. This paper firstly presents the typical procedure of 3D modelling methods and then reviews the previous work of 3D geometrical modelling techniques and systems developed for industrial, medical and animation applications. Especially the paper discusses the problems associated with the existing techniques and systems when they are applied to 3D modelling of biological systems. Based upon the discussions, the paper proposes some areas of research interests in 3D modelling of biological systems and for Biomimetics.
Eck, Simon; Wörz, Stefan; Müller-Ott, Katharina; Hahn, Matthias; Biesdorf, Andreas; Schotta, Gunnar; Rippe, Karsten; Rohr, Karl
2016-08-01
The genome is partitioned into regions of euchromatin and heterochromatin. The organization of heterochromatin is important for the regulation of cellular processes such as chromosome segregation and gene silencing, and their misregulation is linked to cancer and other diseases. We present a model-based approach for automatic 3D segmentation and 3D shape analysis of heterochromatin foci from 3D confocal light microscopy images. Our approach employs a novel 3D intensity model based on spherical harmonics, which analytically describes the shape and intensities of the foci. The model parameters are determined by fitting the model to the image intensities using least-squares minimization. To characterize the 3D shape of the foci, we exploit the computed spherical harmonics coefficients and determine a shape descriptor. We applied our approach to 3D synthetic image data as well as real 3D static and real 3D time-lapse microscopy images, and compared the performance with that of previous approaches. It turned out that our approach yields accurate 3D segmentation results and performs better than previous approaches. We also show that our approach can be used for quantifying 3D shape differences of heterochromatin foci. PMID:27037463
Support Vector Machine active learning for 3D model retrieval
无
2007-01-01
In this paper, we present a novel Support Vector Machine active learning algorithm for effective 3D model retrieval using the concept of relevance feedback. The proposed method learns from the most informative objects which are marked by the user, and then creates a boundary separating the relevant models from irrelevant ones. What it needs is only a small number of 3D models labelled by the user. It can grasp the user's semantic knowledge rapidly and accurately. Experimental results showed that the proposed algorithm significantly improves the retrieval effectiveness. Compared with four state-of-the-art query refinement schemes for 3D model retrieval, it provides superior retrieval performance after no more than two rounds of relevance feedback.
Chau, Chieu Vinh
2007-01-01
The interest for a detailed and high solution city model has been large within the project” Optical signature analysis” at the department for Sensor Technology in FOI, Linköping. Thus, a textured 3D-model over Norrköping is needed, which later can be imported into simulation software to study optical signature in urban environment. The aim with this thesis work is to be able to use the result as a multi-used 3D-model within applications of the Swedish defence force for future usage. It is imp...
Modeling real conditions of 'Ukrytie' object in 3D measurement
The article covers a technology of creation on soft products basis for designing: AutoCad, and computer graphics and animation 3D Studio, 3DS MAX, of 3D model of geometrical parameters of current conditions of building structures, technological equipment, fuel-containing materials, concrete, water of ruined Unit 4, 'Ukryttia' object, of Chernobyl NPP. The model built using the above technology will be applied in the future as a basis when automating the design and computer modeling of processes at the 'Ukryttia' object
Potential of 3D City Models to assess flood vulnerability
Schröter, Kai; Bochow, Mathias; Schüttig, Martin; Nagel, Claus; Ross, Lutz; Kreibich, Heidi
2016-04-01
Vulnerability, as the product of exposure and susceptibility, is a key factor of the flood risk equation. Furthermore, the estimation of flood loss is very sensitive to the choice of the vulnerability model. Still, in contrast to elaborate hazard simulations, vulnerability is often considered in a simplified manner concerning the spatial resolution and geo-location of exposed objects as well as the susceptibility of these objects at risk. Usually, area specific potential flood loss is quantified on the level of aggregated land-use classes, and both hazard intensity and resistance characteristics of affected objects are represented in highly simplified terms. We investigate the potential of 3D City Models and spatial features derived from remote sensing data to improve the differentiation of vulnerability in flood risk assessment. 3D City Models are based on CityGML, an application scheme of the Geography Markup Language (GML), which represents the 3D geometry, 3D topology, semantics and appearance of objects on different levels of detail. As such, 3D City Models offer detailed spatial information which is useful to describe the exposure and to characterize the susceptibility of residential buildings at risk. This information is further consolidated with spatial features of the building stock derived from remote sensing data. Using this database a spatially detailed flood vulnerability model is developed by means of data-mining. Empirical flood damage data are used to derive and to validate flood susceptibility models for individual objects. We present first results from a prototype application in the city of Dresden, Germany. The vulnerability modeling based on 3D City Models and remote sensing data is compared i) to the generally accepted good engineering practice based on area specific loss potential and ii) to a highly detailed representation of flood vulnerability based on a building typology using urban structure types. Comparisons are drawn in terms of
3D head model classification using optimized EGI
Tong, Xin; Wong, Hau-san; Ma, Bo
2006-02-01
With the general availability of 3D digitizers and scanners, 3D graphical models have been used widely in a variety of applications. This has led to the development of search engines for 3D models. Especially, 3D head model classification and retrieval have received more and more attention in view of their many potential applications in criminal identifications, computer animation, movie industry and medical industry. This paper addresses the 3D head model classification problem using 2D subspace analysis methods such as 2D principal component analysis (2D PCA[3]) and 2D fisher discriminant analysis (2DLDA[5]). It takes advantage of the fact that the histogram is a 2D image, and we can extract the most useful information from these 2D images to get a good result accordingingly. As a result, there are two main advantages: First, we can perform less calculation to obtain the same rate of classification; second, we can reduce the dimensionality more than PCA to obtain a higher efficiency.
Development of hybrid 3-D hydrological modeling for the NCAR Community Earth System Model (CESM)
Zeng, Xubin [Univ. of Arizona, Tucson, AZ (United States); Troch, Peter [Univ. of Arizona, Tucson, AZ (United States); Pelletier, Jon [Univ. of Arizona, Tucson, AZ (United States); Niu, Guo-Yue [Univ. of Arizona, Tucson, AZ (United States); Gochis, David [NCAR Research Applications Lab., Boulder, CO (United States)
2015-11-15
This is the Final Report of our four-year (3-year plus one-year no cost extension) collaborative project between the University of Arizona (UA) and the National Center for Atmospheric Research (NCAR). The overall objective of our project is to develop and evaluate the first hybrid 3-D hydrological model with a horizontal grid spacing of 1 km for the NCAR Community Earth System Model (CESM).
3D model of amphioxus steroid receptor complexed with estradiol
The origins of signaling by vertebrate steroids are not fully understood. An important advance was the report that an estrogen-binding steroid receptor [SR] is present in amphioxus, a basal chordate with a similar body plan as vertebrates. To investigate the evolution of estrogen-binding to steroid receptors, we constructed a 3D model of amphioxus SR complexed with estradiol. This 3D model indicates that although the SR is activated by estradiol, some interactions between estradiol and human ERα are not conserved in the SR, which can explain the low affinity of estradiol for the SR. These differences between the SR and ERα in the steroid-binding domain are sufficient to suggest that another steroid is the physiological regulator of the SR. The 3D model predicts that mutation of Glu-346 to Gln will increase the affinity of testosterone for amphioxus SR and elucidate the evolution of steroid-binding to nuclear receptors.
Statistical 3D damage accumulation model for ion implant simulators
Hernandez-Mangas, J M; Enriquez, L E; Bailon, L; Barbolla, J; Jaraiz, M
2003-01-01
A statistical 3D damage accumulation model, based on the modified Kinchin-Pease formula, for ion implant simulation has been included in our physically based ion implantation code. It has only one fitting parameter for electronic stopping and uses 3D electron density distributions for different types of targets including compound semiconductors. Also, a statistical noise reduction mechanism based on the dose division is used. The model has been adapted to be run under parallel execution in order to speed up the calculation in 3D structures. Sequential ion implantation has been modelled including previous damage profiles. It can also simulate the implantation of molecular and cluster projectiles. Comparisons of simulated doping profiles with experimental SIMS profiles are presented. Also comparisons between simulated amorphization and experimental RBS profiles are shown. An analysis of sequential versus parallel processing is provided.
3D subsurface temperature model of Europe for geothermal exploration
Limberger, J.; Wees, J.D. van
2014-01-01
For the assessment of geothermal resources in Europe we constructed a digital 3D temperature model of the European crust and sedimentary basins, incorporating publicly available temperature data. Using European crustal thickness models and indirect parameters such as surface heat flow measurements,
Diffusion approximation for modeling of 3-D radiation distributions
A three-dimensional transport code DIF3D, based on the diffusion approximation, is used to model the spatial distribution of radiation energy arising from volumetric isotropic sources. Future work will be concerned with the determination of irradiances and modeling of realistic scenarios, relevant to the battlefield conditions. 8 refs., 4 figs
3D Shape Modeling Using High Level Descriptors
Andersen, Vedrana
The goal of this Ph.D. project is to investigate and improve the methods for describing the surface of 3D objects, with focus on modeling geometric texture on surfaces. Surface modeling being a large field of research, the work done during this project concentrated around a few smaller areas...
Validation of a 3-D hemispheric nested air pollution model
Frohn, L. M.; Christensen, J.H.; Brandt, J; C. Geels; Hansen, K. M.
2003-01-01
Several air pollution transport models have been developed at the National Environmental Research Institute in Denmark over the last decade (DREAM, DEHM, ACDEP and DEOM). A new 3-D nested Eulerian transport-chemistry model: REGIonal high resolutioN Air pollution model (REGINA) is based on modules and parameterisations from these models as well as new methods. The model covers the majority of the Northern Hemisphere with currently one nest...
ENHANCED LOD CONCEPTS FOR VIRTUAL 3D CITY MODELS
Benner, J.; Geiger, A; G. Gröger; Häfele, K.-H.; Löwner, M.-O.
2013-01-01
Virtual 3D city models contain digital three dimensional representations of city objects like buildings, streets or technical infrastructure. Because size and complexity of these models continuously grow, a Level of Detail (LoD) concept effectively supporting the partitioning of a complete model into alternative models of different complexity and providing metadata, addressing informational content, complexity and quality of each alternative model is indispensable. After a short over...
Round table session on '3D-city-modeling'
Rüdiger, Bjarne; Tournay, Bruno
According to eCAADe's mission, the exchange and collaboration within the area of computer aided architectural design education and research, while respecting the pedagogical and administrative approaches in the different schools and countries, can be regarded as a core activity. On the occasion of...... eCAADe 2001 in Helsinki a working session on the topic "3D-City-Modeling" was held, in which a varietybundle of papers was presented. The eCAADe 2002 round table session on "3D-City-Modeling" is opening up for an intensive discussion on a number of goals which were elaborated by a working group in...
Round table session on '3D-city-modeling
Rüdiger, Bjarne; Tournay, Bruno
According to eCAADs's mission, the exchange and collaboration within the area of computer aided architectural design education and research, while respecting the pedagogical and administrative approaches in the different schools and countries, can be regarded as a core activity. On the occasion of...... eCAADe 2001 in Helsinki a working session on the topic "3D-City-Modeling" was held, in which a varietybundle of papers was presented. The eCAADe 2002 round table session on "3D-City-Modeling" is opening up for an intensive discussion on a number of goals which were elaborated by a working group in...
Modelling Gaia CCD pixels with Silvaco 3D engineering software
Seabroke, G. M.; Prod'Homme, T.; Hopkinson, G.; Burt, D.; Robbins, M.; Holland, A.
2011-02-01
Gaia will only achieve its unprecedented measurement accuracy requirements with detailed calibration and correction for radiation damage. We present our Silvaco 3D engineering software model of the Gaia CCD pixel and two of its applications for Gaia: (1) physically interpreting supplementary buried channel (SBC) capacity measurements (pocket-pumping and first pixel response) in terms of e2v manufacturing doping alignment tolerances; and (2) deriving electron densities within a charge packet as a function of the number of constituent electrons and 3D position within the charge packet as input to microscopic models being developed to simulate radiation damage.
Design and modeling for 3D ICS and interposers
Swaminathan, Madhavan
2013-01-01
3D Integration is being touted as the next semiconductor revolution. This book provides a comprehensive coverage on the design and modeling aspects of 3D integration, in particularly, focus on its electrical behavior. Looking from the perspective the Silicon Via (TSV) and Glass Via (TGV) technology, the book introduces 3DICs and Interposers as a technology, and presents its application in numerical modeling, signal integrity, power integrity and thermal integrity. The authors underscored the potential of this technology in design exchange formats and power distribution.
Automatic Generation of 3D Building Models with Multiple Roofs
Kenichi Sugihara; Yoshitugu Hayashi
2008-01-01
Based on building footprints (building polygons) on digital maps, we are proposing the GIS and CG integrated system that automatically generates 3D building models with multiple roofs. Most building polygons' edges meet at right angles (orthogonal polygon). The integrated system partitions orthogonal building polygons into a set of rectangles and places rectangular roofs and box-shaped building bodies on these rectangles. In order to partition an orthogonal polygon, we proposed a useful polygon expression in deciding from which vertex a dividing line is drawn. In this paper, we propose a new scheme for partitioning building polygons and show the process of creating 3D roof models.
Modelling Gaia CCD pixels with Silvaco 3D engineering software
Seabroke, G M; Hopkinson, G; Burt, D; Robbins, M; Holland, A
2010-01-01
Gaia will only achieve its unprecedented measurement accuracy requirements with detailed calibration and correction for radiation damage. We present our Silvaco 3D engineering software model of the Gaia CCD pixel and two of its applications for Gaia: (1) physically interpreting supplementary buried channel (SBC) capacity measurements (pocket-pumping and first pixel response) in terms of e2v manufacturing doping alignment tolerances; and (2) deriving electron densities within a charge packet as a function of the number of constituent electrons and 3D position within the charge packet as input to microscopic models being developed to simulate radiation damage.
Probabilistic reasoning for assembly-based 3D modeling
Chaudhuri, Siddhartha
2011-01-01
Assembly-based modeling is a promising approach to broadening the accessibility of 3D modeling. In assembly-based modeling, new models are assembled from shape components extracted from a database. A key challenge in assembly-based modeling is the identification of relevant components to be presented to the user. In this paper, we introduce a probabilistic reasoning approach to this problem. Given a repository of shapes, our approach learns a probabilistic graphical model that encodes semantic and geometric relationships among shape components. The probabilistic model is used to present components that are semantically and stylistically compatible with the 3D model that is being assembled. Our experiments indicate that the probabilistic model increases the relevance of presented components. © 2011 ACM.
Parallel Optimization of 3D Cardiac Electrophysiological Model Using GPU
Yong Xia
2015-01-01
Full Text Available Large-scale 3D virtual heart model simulations are highly demanding in computational resources. This imposes a big challenge to the traditional computation resources based on CPU environment, which already cannot meet the requirement of the whole computation demands or are not easily available due to expensive costs. GPU as a parallel computing environment therefore provides an alternative to solve the large-scale computational problems of whole heart modeling. In this study, using a 3D sheep atrial model as a test bed, we developed a GPU-based simulation algorithm to simulate the conduction of electrical excitation waves in the 3D atria. In the GPU algorithm, a multicellular tissue model was split into two components: one is the single cell model (ordinary differential equation and the other is the diffusion term of the monodomain model (partial differential equation. Such a decoupling enabled realization of the GPU parallel algorithm. Furthermore, several optimization strategies were proposed based on the features of the virtual heart model, which enabled a 200-fold speedup as compared to a CPU implementation. In conclusion, an optimized GPU algorithm has been developed that provides an economic and powerful platform for 3D whole heart simulations.
Geospatial Modelling Approach for 3d Urban Densification Developments
Koziatek, O.; Dragićević, S.; Li, S.
2016-06-01
With growing populations, economic pressures, and the need for sustainable practices, many urban regions are rapidly densifying developments in the vertical built dimension with mid- and high-rise buildings. The location of these buildings can be projected based on key factors that are attractive to urban planners, developers, and potential buyers. Current research in this area includes various modelling approaches, such as cellular automata and agent-based modelling, but the results are mostly linked to raster grids as the smallest spatial units that operate in two spatial dimensions. Therefore, the objective of this research is to develop a geospatial model that operates on irregular spatial tessellations to model mid- and high-rise buildings in three spatial dimensions (3D). The proposed model is based on the integration of GIS, fuzzy multi-criteria evaluation (MCE), and 3D GIS-based procedural modelling. Part of the City of Surrey, within the Metro Vancouver Region, Canada, has been used to present the simulations of the generated 3D building objects. The proposed 3D modelling approach was developed using ESRI's CityEngine software and the Computer Generated Architecture (CGA) language.
Mirko Borisov
2014-12-01
Full Text Available U radu se opisuju 3D modeli geopodataka i njihova primjena. Na geodetskim planovima i topografskim kartama najčešće se primjenjuju metode prikaza terena (reljefa pomoću kota i izohipsi. Međutim, sa pojavom novih tehnologija mijenja se način vizualizacije i naglašava koncept 3D modela geopodataka. Pritom, koriste se različiti pojmovi: digitalni model visina (DMV, digitalni model terena (DMT, digitalni model površi (DMP i drugo. Infrastruktura i 3D modeli geopodataka su standardizovani, ali se vizualizacija i detaljnost sadržaja mijenja i usklađuje prema namjeni i razmjeri prikaza. Primjena 3D modela geopodataka u digitalnom obliku (raster ili vektor postaje sve više aktuelna i putem interneta. Zato je važno razlikovati navedene pojmove i odlike 3D modela geopodataka kao i mogućnosti njihove primjene. : This paper describes the 3D geodata models and their application. On geodetic plans and topographic maps commonly applied methods of terrain (relief by spots elevation and contour lines. However, with the advent of new technologies the way of the visualisation is changing and highlights the concept 3D geodata model. Namely, there are different concepts: digital elevation model (DEM, digital terrain model (DTM, digital surface model (DSP and so on. Infrastructure and 3D geodata models are standardized, while the visualization and details of information change and adjust the needs and aspect ratio display. Application of 3D geodata models in digital format (raster or vector is becoming increasingly topical over the internet. Therefore, it is important to distinguish between certain concepts and features of 3D geodata models and the possibility of their application.
3D Model Generation From the Engineering Drawing
Vaský, Jozef; Eliáš, Michal; Bezák, Pavol; Červeňanská, Zuzana; Izakovič, Ladislav
2010-01-01
The contribution deals with the transformation of engineering drawings in a paper form into a 3D computer representation. A 3D computer model can be further processed in CAD/CAM system, it can be modified, archived, and a technical drawing can be then generated from it as well. The transformation process from paper form to the data one is a complex and difficult one, particularly owing to the different types of drawings, forms of displayed objects and encountered errors and deviations from technical standards. The algorithm for 3D model generating from an orthogonal vector input representing a simplified technical drawing of the rotational part is described in this contribution. The algorithm was experimentally implemented as ObjectARX application in the AutoCAD system and the test sample as the representation of the rotational part was used for verificaton.
Robust model-based 3d/3D fusion using sparse matching for minimally invasive surgery.
Neumann, Dominik; Grbic, Sasa; John, Matthias; Navab, Nassir; Hornegger, Joachim; Ionasec, Razvan
2013-01-01
Classical surgery is being disrupted by minimally invasive and transcatheter procedures. As there is no direct view or access to the affected anatomy, advanced imaging techniques such as 3D C-arm CT and C-arm fluoroscopy are routinely used for intra-operative guidance. However, intra-operative modalities have limited image quality of the soft tissue and a reliable assessment of the cardiac anatomy can only be made by injecting contrast agent, which is harmful to the patient and requires complex acquisition protocols. We propose a novel sparse matching approach for fusing high quality pre-operative CT and non-contrasted, non-gated intra-operative C-arm CT by utilizing robust machine learning and numerical optimization techniques. Thus, high-quality patient-specific models can be extracted from the pre-operative CT and mapped to the intra-operative imaging environment to guide minimally invasive procedures. Extensive quantitative experiments demonstrate that our model-based fusion approach has an average execution time of 2.9 s, while the accuracy lies within expert user confidence intervals. PMID:24505663
Causal Dynamical Triangulation of 3D Tensor Model
Kawabe, Hiroshi
2016-01-01
We extend the string field theory of the two dimensional (2D) generalized causal dynamical triangulation (GCDT) with the Ishibashi-Kawai (IK-) type interaction formulated by the matrix model, to the three dimensional (3D) model of the surface field theory. Based on the loop gas model, we construct a tensor model for the discretized surface field and then apply it the stochastic quantization method. In the double scaling limit, the model is characterized by two scaling dimensions $D$ and $D_N$, the power indices of the minimal length as the scaling parameter. The continuum GCDT model with the IK-type interaction is realized with the similar restriction in the $D_N$-$D$ space, to the 2D model. The distinct property in the 3D model is that the quantum effect contains the IK-type interaction only, while the ordinary splitting interaction is excluded.
Geodiversity: Exploration of 3D geological model space
Lindsay, M. D.; Jessell, M. W.; Ailleres, L.; Perrouty, S.; de Kemp, E.; Betts, P. G.
2013-05-01
The process of building a 3D model necessitates the reconciliation of field observations, geophysical interpretation, geological data uncertainty and the prevailing tectonic evolution hypotheses and interpretations. Uncertainty is compounded when clustered data points collected at local scales are statistically upscaled to one or two points for use in regional models. Interpretation is required to interpolate between sparse field data points using ambiguous geophysical data in covered terranes. It becomes clear that multiple interpretations are possible during model construction. The various interpretations are considered as potential natural representatives, but pragmatism typically dictates that just a single interpretation is offered by the modelling process. Uncertainties are introduced into the 3D model during construction from a variety of sources and through data set optimisation that produces a single model. Practices such as these are likely to result in a model that does not adequately represent the target geology. A set of geometrical ‘geodiversity’ metrics are used to analyse a 3D model of the Gippsland Basin, southeastern Australia after perturbing geological input data via uncertainty simulation. The resulting sets of perturbed geological observations are used to calculate a suite of geological 3D models that display a range of geological architectures. The concept of biodiversity has been adapted for the geosciences to quantify geometric variability, or geodiversity, between models in order to understand the effect uncertainty has models geometry. Various geometrical relationships (depth, volume, contact surface area, curvature and geological complexity) are used to describe the range of possibilities exhibited throughout the model suite. End-member models geodiversity metrics are classified in a similar manner to taxonomic descriptions. Further analysis of the model suite is performed using principal component analysis (PCA) to determine
Sharkawi, K.-H.; Abdul-Rahman, A.
2013-09-01
Cities and urban areas entities such as building structures are becoming more complex as the modern human civilizations continue to evolve. The ability to plan and manage every territory especially the urban areas is very important to every government in the world. Planning and managing cities and urban areas based on printed maps and 2D data are getting insufficient and inefficient to cope with the complexity of the new developments in big cities. The emergence of 3D city models have boosted the efficiency in analysing and managing urban areas as the 3D data are proven to represent the real world object more accurately. It has since been adopted as the new trend in buildings and urban management and planning applications. Nowadays, many countries around the world have been generating virtual 3D representation of their major cities. The growing interest in improving the usability of 3D city models has resulted in the development of various tools for analysis based on the 3D city models. Today, 3D city models are generated for various purposes such as for tourism, location-based services, disaster management and urban planning. Meanwhile, modelling 3D objects are getting easier with the emergence of the user-friendly tools for 3D modelling available in the market. Generating 3D buildings with high accuracy also has become easier with the availability of airborne Lidar and terrestrial laser scanning equipments. The availability and accessibility to this technology makes it more sensible to analyse buildings in urban areas using 3D data as it accurately represent the real world objects. The Open Geospatial Consortium (OGC) has accepted CityGML specifications as one of the international standards for representing and exchanging spatial data, making it easier to visualize, store and manage 3D city models data efficiently. CityGML able to represents the semantics, geometry, topology and appearance of 3D city models in five well-defined Level-of-Details (LoD), namely LoD0
Estimation of shape model parameters for 3D surfaces
Erbou, Søren Gylling Hemmingsen; Darkner, Sune; Fripp, Jurgen; Ourselin, Sébastien; Ersbøll, Bjarne Kjær
surfaces using distance maps, which enables the estimation of model parameters without the requirement of point correspondence. For applications with acquisition limitations such as speed and cost, this formulation enables the fitting of a statistical shape model to arbitrarily sampled data. The method is......Statistical shape models are widely used as a compact way of representing shape variation. Fitting a shape model to unseen data enables characterizing the data in terms of the model parameters. In this paper a Gauss-Newton optimization scheme is proposed to estimate shape model parameters of 3D...... applied to a database of 3D surfaces from a section of the porcine pelvic bone extracted from 33 CT scans. A leave-one-out validation shows that the parameters of the first 3 modes of the shape model can be predicted with a mean difference within [-0.01,0.02] from the true mean, with a standard deviation...
Teaching the geological subsurface with 3D models
Thorpe, Steve; Ward, Emma
2014-05-01
3D geological models have great potential as a resource when teaching geological concepts as it allows the student to visualise and interrogate UK geology. They are especially useful when dealing with the conversion of 2D field, map and GIS outputs into three dimensional geological units, which is a common problem for many students. Today's earth science students use a variety of skills and processes during their learning experience including spatial thinking, image construction, detecting patterns, making predictions and deducing the orientation of themselves. 3D geological models can reinforce spatial thinking strategies and encourage students to think about processes and properties, in turn helping the student to recognise pre-learnt geological principles in the field and to convert what they see at the surface into a picture of what is going on at depth. The British Geological Survey (BGS) has been producing digital 3D geological models for over 10 years. The models produced are revolutionising the working practices, data standards and products of the BGS. Sharing our geoscience information with academia is highlighted throughout the BGS strategy as is instilling practical skills in future geoscience professionals, such as model building and interpretation. In 2009 a project was launched to investigate the potential of the models as a teaching resource. The study included justifying if and how the models help students to learn, how models have been used historically, and how other forms of modelling are being used today. BGS now produce 3D geological models for use by anyone teaching or learning geoscience. They incorporate educational strategies that will develop geospatial skills and alleviate potential problems that some students experience. They are contained within contemporary case studies and show standard geological concepts, structures, sedimentary rocks, cross sections and field techniques. 3D geological models of the Isle of Wight and Ingleborough
3D Geological Model for "LUSI" - a Deep Geothermal System
Sohrabi, Reza; Jansen, Gunnar; Mazzini, Adriano; Galvan, Boris; Miller, Stephen A.
2016-04-01
Geothermal applications require the correct simulation of flow and heat transport processes in porous media, and many of these media, like deep volcanic hydrothermal systems, host a certain degree of fracturing. This work aims to understand the heat and fluid transport within a new-born sedimentary hosted geothermal system, termed Lusi, that began erupting in 2006 in East Java, Indonesia. Our goal is to develop conceptual and numerical models capable of simulating multiphase flow within large-scale fractured reservoirs such as the Lusi region, with fractures of arbitrary size, orientation and shape. Additionally, these models can also address a number of other applications, including Enhanced Geothermal Systems (EGS), CO2 sequestration (Carbon Capture and Storage CCS), and nuclear waste isolation. Fractured systems are ubiquitous, with a wide-range of lengths and scales, making difficult the development of a general model that can easily handle this complexity. We are developing a flexible continuum approach with an efficient, accurate numerical simulator based on an appropriate 3D geological model representing the structure of the deep geothermal reservoir. Using previous studies, borehole information and seismic data obtained in the framework of the Lusi Lab project (ERC grant n°308126), we present here the first 3D geological model of Lusi. This model is calculated using implicit 3D potential field or multi-potential fields, depending on the geological context and complexity. This method is based on geological pile containing the geological history of the area and relationship between geological bodies allowing automatic computation of intersections and volume reconstruction. Based on the 3D geological model, we developed a new mesh algorithm to create hexahedral octree meshes to transfer the structural geological information for 3D numerical simulations to quantify Thermal-Hydraulic-Mechanical-Chemical (THMC) physical processes.
APROS 3-D core models for simulators and plant analyzers
The 3-D core models of APROS simulation environment can be used in simulator and plant analyzer applications, as well as in safety analysis. The key feature of APROS models is that the same physical models can be used in all applications. For three-dimensional reactor cores the APROS models cover both quadratic BWR and PWR cores and the hexagonal lattice VVER-type cores. In APROS environment the user can select the number of flow channels in the core and either five- or six-equation thermal hydraulic model for these channels. The thermal hydraulic model and the channel description have a decisive effect on the calculation time of the 3-D core model and thus just these selection make at present the major difference between a safety analysis model and a training simulator model. The paper presents examples of various types of 3-D LWR-type core descriptions for simulator and plant analyzer use and discusses the differences of calculation speed and physical results between a typical safety analysis model description and a real-time simulator model description in transients. (author)
Deb, S. K.; Kishtawal, C. M.; Kumar, Prashant; Kiran Kumar, A. S.; Pal, P. K.; Kaushik, Nitesh; Sangar, Ghansham
2016-03-01
The advanced Indian meteorological geostationary satellite INSAT-3D was launched on 26 July 2013 with an improved imager and an infrared sounder and is placed at 82°E over the Indian Ocean region. With the advancement in retrieval techniques of different atmospheric parameters and with improved imager data have enhanced the scope for better understanding of the different tropical atmospheric processes over this region. The retrieval techniques and accuracy of one such parameter, Atmospheric Motion Vectors (AMV) has improved significantly with the availability of improved spatial resolution data along with more options of spectral channels in the INSAT-3D imager. The present work is mainly focused on providing brief descriptions of INSAT-3D data and AMV derivation processes using these data. It also discussed the initial quality assessment of INSAT-3D AMVs for a period of six months starting from 01 February 2014 to 31 July 2014 with other independent observations: i) Meteosat-7 AMVs available over this region, ii) in-situ radiosonde wind measurements, iii) cloud tracked winds from Multi-angle Imaging Spectro-Radiometer (MISR) and iv) numerical model analysis. It is observed from this study that the qualities of newly derived INSAT-3D AMVs are comparable with existing two versions of Meteosat-7 AMVs over this region. To demonstrate its initial application, INSAT-3D AMVs are assimilated in the Weather Research and Forecasting (WRF) model and it is found that the assimilation of newly derived AMVs has helped in reduction of track forecast errors of the recent cyclonic storm NANAUK over the Arabian Sea. Though, the present study is limited to its application to one case study, however, it will provide some guidance to the operational agencies for implementation of this new AMV dataset for future applications in the Numerical Weather Prediction (NWP) over the south Asia region.
Monocular model-based 3D tracking of rigid objects
Lepetit, Vincent
2014-01-01
Many applications require tracking complex 3D objects. These include visual serving of robotic arms on specific target objects, Augmented Reality systems that require real time registration of the object to be augmented, and head tracking systems that sophisticated interfaces can use. Computer vision offers solutions that are cheap, practical and non-invasive. ""Monocular Model-Based 3D Tracking of Rigid Objects"" reviews the different techniques and approaches that have been developed by industry and research. First, important mathematical tools are introduced: camera representation, robust e
Automatic 3D Modeling of the Urban Landscape
Esteban, I.; Dijk, J.; Groen, F.A.
2010-01-01
In this paper we present a fully automatic system for building 3D models of urban areas at the street level. We propose a novel approach for the accurate estimation of the scale consistent camera pose given two previous images. We employ a new method for global optimization and use a novel sampling
3D Property Modeling of Void Ratio by Cokriging
Yao Lingqing; Pan Mao; Cheng Qiuming
2008-01-01
Void ratio measures compactness of ground soil in geotechnical engineering. When samples are collected in certain area for mapping void ratios, other relevant types of properties such as water content may be also analyzed. To map the spatial distribution of void ratio in the area based on these types of point, observation data interpolation is often needed. Owing to the variance of sampling density along the horizontal and vertical directions, special consideration is required to handle anisotropy of estimator. 3D property modeling aims at predicting the overall distribution of property values from limited samples, and geostatistical method can he employed naturally here because they help to minimize the mean square error of estimation. To construct 3D property model of void ratio, cokriging was used considering its mutual correlation with water content, which is another important soil parameter. Moreover, K-D tree was adopted to organize the samples to accelerate neighbor query in 3D space during the above modeling process. At last, spatial configuration of void ratio distribution in an engineering body was modeled through 3D visualization, which provides important information for civil engineering purpose.
Building a 3-D Appearance Model of the Human Face
Sjöstrand, Karl; Larsen, Rasmus; Lading, Brian
2003-01-01
This paper describes a method for building an appearance model from three-dimensional data of human faces. The data consists of 3-D vertices, polygons and a texture map. The method uses a set of nine manually placed landmarks to automatically form a dense correspondence of thousands of points. This makes sure the model is able to capture the subtle details of a face. The model can be used for face segmentation and fully automated face registration.
Building a 3-D Appearance Model of the Human Face
Sjöstrand, Karl; Larsen, Rasmus; Lading, Brian
2003-01-01
This paper describes a method for building an appearance model from three-dimensional data of human faces. The data consists of 3-D vertices, polygons and a texture map. The method uses a set of nine manually placed landmarks to automatically form a dense correspondence of thousands of points. This...... makes sure the model is able to capture the subtle details of a face. The model can be used for face segmentation and fully automated face registration....
Thermal 3D Modeling of Geothermal Area Using Terrestrial Photogrammetry
Akcay, Ozgun; Cuneyt Erenoglu, Ramazan; Erenoglu, Oya; Yılmazturk, Ferruh; Karaca, Zeki
2015-04-01
Photogrammetry and computer vision, sciences producing high accuracy 3D models from digital images based on projective geometry. 3D models can also be produced using thermal camera images using photogrammetry and computer vision techniques. Thermal images are capable of displaying hotspots on geothermal areas as a heat source in details. In the research, Tuzla geothermal area in Çanakkale province of Turkey is inspected using imaging techniques of terrestrial photogrammetry. Both a digital camera Canon EOS 650D and an infrared camera Optris PI 450 are used to obtain images of the thermal site. Calibration parameters (focal length, principle point, distortion coefficients) of thermal and digital cameras are determined using the calibration test field at the laboratory before the field work. In order to provide the georeferencing and the robustness of the 3D model, aluminum discs having diameter of 30 centimeters as ground control points (GCPs) are set to the geothermal area appropriately before imaging. Aluminum targets are chosen as the GCP because they are determined on the image depending on the contrast reflectance rate of the aluminum. Using GNSS RTK receivers supplying ±1 cm accuracy positioning, GCPs are measured so as to implement photogrammetric process successfully with thermal images. Numerous corresponding points are detected on the overlapped images with image matching techniques. Later on, bundle block adjustment is applied to calculate the revised interior orientation parameters of camera and exterior orientation parameters of camera positions. The 3D model showing details of the surface temperatures of the geothermal area are produced with multi view stereo (MVS) technique. The technique is able to produce 3D representation (point cloud, mesh and textured surface) of the field from both the thermal and digital images. The research presents that photogrammetric evaluation of thermal images is a noteworthy method to obtain a quick- accurate 3D
3D geometric modelling of hand-woven textile
Shidanshidi, H.; Naghdy, F.; Naghdy, G.; Conroy, D. Wood
2008-02-01
Geometric modeling and haptic rendering of textile has attracted significant interest over the last decade. A haptic representation is created by adding the physical properties of an object to its geometric configuration. While research has been conducted into geometric modeling of fabric, current systems require time-consuming manual recognition of textile specifications and data entry. The development of a generic approach for construction of the 3D geometric model of a woven textile is pursued in this work. The geometric model would be superimposed by a haptic model in the future work. The focus at this stage is on hand-woven textile artifacts for display in museums. A fuzzy rule based algorithm is applied to the still images of the artifacts to generate the 3D model. The derived model is exported as a 3D VRML model of the textile for visual representation and haptic rendering. An overview of the approach is provided and the developed algorithm is described. The approach is validated by applying the algorithm to different textile samples and comparing the produced models with the actual structure and pattern of the samples.
Use Models like Maps in a 3D SDI
Gietzel, Jan; Gabriel, Paul; Schaeben, Helmut; Le, Hai Ha
2013-04-01
Digital geological applications have become 3D up to 4D modelling of the underground. The modellers are working very heterogeneously in terms of its applied software systems. On the other hand the 3D/4D modelling of the subsurface has become part of the geological surveys all around the world. This implies a wide spread group of users working in different institutions aiming to work together on one subsurface model. Established 3D/4D-modelling software systems mainly use a file based approach to store data, which is in a high contrast to the needs of a central administrated and network based data transfer approach. At the department of geophysics and geo information sciences at the Technical University Bergakademie Freiberg, the GST system for managing 3D and 4D geosciences data in a databases system was developed and is now continued by the company GiGa infosystems. The GST-Framework includes a storage engine, a web service for sharing and a number of client software including a browser based client interface for visualising, accessing and manipulating geological CAD data. Including a check out system GST supports multi user editing on huge models, designed to manage seamless high resolution models of the subsurface. While working on complex projects various software is used for the creation of the model, the prediction of properties and final simulation. A problem rising from the use of several software is the interoperability of the models. Due to conversion errors different working groups use mainly different raw data. This results in different models, which have to be corrected with additional effort. One platform sharing the models is strongly demanded. One high potential solution is a centralized and software independent storage, which will be presented.
Statistical skull models from 3D X-ray images
Berar, M; Bailly, G; Payan, Y; Berar, Maxime; Desvignes, Michel; Payan, Yohan
2006-01-01
We present 2 statistical models of the skull and mandible built upon an elastic registration method of 3D meshes. The aim of this work is to relate degrees of freedom of skull anatomy, as static relations are of main interest for anthropology and legal medicine. Statistical models can effectively provide reconstructions together with statistical precision. In our applications, patient-specific meshes of the skull and the mandible are high-density meshes, extracted from 3D CT scans. All our patient-specific meshes are registrated in a subject-shared reference system using our 3D-to-3D elastic matching algorithm. Registration is based upon the minimization of a distance between the high density mesh and a shared low density mesh, defined on the vertexes, in a multi resolution approach. A Principal Component analysis is performed on the normalised registrated data to build a statistical linear model of the skull and mandible shape variation. The accuracy of the reconstruction is under the millimetre in the shape...
Anisotropic 3D Modeling for Long Offset VSP Survey Design
Today's seismic techniques allow the geoscientist to do the interpretation more quantitatively. AVO and anisotropy measurements are the examples of DHI (Direct Hydrocarbon Indication). These measurements can be done accurately using long offset borehole seismic survey such as walk away VSP, having the geophones located down hole close to the target formation. This paper will show the importance 3D seismic modeling prior to the survey, by simulating the seismic wave propagation in three-dimensional volume filled with continuous material properties. This pre-survey modeling can help us suppressing the uncertainties and narrowing the error bars on the real survey. Some examples from offshore Nigeria showed dramatic geometrical differences between ordinary 2D compared to 3D observations Assumption that the seismic wave travels in 2D plane is not always acceptable for survey design. The examples also demonstrated the ability to observe some critical information such as the limit of incidence angle, compromise between resolution and image coverage, effects of velocity anomalies, anisotropy and dipping formations on lateral coverage. Fluid effect in 3D modeling will also be discussed here. Amplitude anomalies are predicted by replacing different type of fluids effect in the target reservoirs, as well as various types of AVO classes. A well-prepared long offset VSP survey is very critical to provide us high quality and high accuracy information that can be used to calibrate and optimise the full 3D seismic processing and interpretation in the area. This process is known as Well Driven Seismic (WDS)
3D Geological modelling - towards a European level infrastructure
Lee, Kathryn A.; van der Krogt, Rob; Busschers, Freek S.
2013-04-01
The joint European Geological Surveys are preparing the ground for a "European Geological Data Infrastructure" (EGDI), under the framework of the FP7-project EGDI-Scope. This scoping study, started in June 2012, for a pan-European e-Infrastructure is based on the successes of earlier joint projects including 'OneGeology-Europe' and aims to provide the backbone for serving interoperable, geological data currently held by European Geological Surveys. Also data from past, ongoing and future European projects will be incorporated. The scope will include an investigation of the functional and technical requirements for serving 3D geological models and will look to research the potential for providing a framework to integrate models at different scales, and form a structure for enabling the development of new and innovative model delivery mechanisms. The EGDI-scope project encourages pan-European inter-disciplinary collaboration between all European Geological Surveys. It aims to enhance emerging web based technologies that will facilitate the delivery of geological data to user communities involved in European policy making and international industry, but also to geoscientific research communities and the general public. Therefore, stakeholder input and communication is imperative to the success, as is the collaboration with all the Geological Surveys of Europe. The most important functional and technical requirements for delivery of such information at pan-European level will be derived from exchanges with relevant European stakeholder representatives and providers of geological data. For handling and delivering 3D geological model data the project will need to address a number of strategic issues: • Which are the most important issues and queries for the relevant stakeholders, requiring 3D geological models? How can this be translated to functional requirements for development and design of an integrated European application? • How to handle the very large
Quasi-3D Multi-scale Modeling Framework Development
Arakawa, A.; Jung, J.
2008-12-01
When models are truncated in or near an energetically active range of the spectrum, model physics must be changed as the resolution changes. The model physics of GCMs and that of CRMs are, however, quite different from each other and at present there is no unified formulation of model physics that automatically provides transition between these model physics. The Quasi-3D (Q3D) Multi-scale Modeling Framework (MMF) is an attempt to bridge this gap. Like the recently proposed Heterogeneous Multiscale Method (HMM) (E and Engquist 2003), MMF combines a macroscopic model, GCM, and a microscopic model, CRM. Unlike the traditional multiscale methods such as the multi-grid and adapted mesh refinement techniques, HMM and MMF are for solving multi-physics problems. They share the common objective "to design combined macroscopic-microscopic computational methods that are much more efficient than solving the full microscopic model and at the same time give the information we need" (E et al. 2008). The question is then how to meet this objective in practice, which can be highly problem dependent. In HHM, the efficiency is gained typically by localization of the microscale problem. Following the pioneering work by Grabowski and Smolarkiewicz (1999) and Grabowski (2001), MMF takes advantage of the fact that 2D CRMs are reasonably successful in simulating deep clouds. In this approach, the efficiency is gained by sacrificing the three-dimensionality of cloud-scale motion. It also "localizes" the algorithm through embedding a CRM in each GCM grid box using cyclic boundary condition. The Q3D MMF is an attempt to reduce the expense due to these constraints by partially including the cloud-scale 3D effects and extending the CRM beyond individual GCM grid boxes. As currently formulated, the Q3D MMF is a 4D estimation/prediction framework that combines a GCM with a 3D anelastic cloud-resolving vector vorticity equation model (VVM) applied to a network of horizontal grids. The network
Modeling Perception of 3D Forms Using Fuzzy Knowledge Bases
Achiche, Sofiane; Ahmed, Saeema
the aesthetics of their products are likely to be perceived are of value. In this paper the authors propose an approach to formalize the relationship between geometric information of a 3D object and the intended perception using fuzzy logic. 3D objects (shapes) created by design engineering students...... to evoke a certain perception were analysed. Three different fuzzy logic models, with different input variables, for evaluating massiveness and lightness in a form are proposed. The uthors identified geometric information as inputs of the fuzzy model and developed a set of fuzzy if/then rules to map...... the relationships between the fuzzy sets on each input premise and the output premise. In our case the output premise of the fuzzy logic model is the level of belonging to the design context (perception). An evaluation of how users perceived the shapes was conducted to validate the fuzzy logic models...
Integrated modeling and 3D visualization for mine complex fields
LI Zhong-xue; SUN En-ji; LI Cui-ping; MA Bin
2007-01-01
Proposed a novel approach to the problem of mine complex fields in a perspective of digital modeling and visual representation, and it aimed at developing a theoretical framework for mine complex fields with the factors and their relationships delineated in a unified manner and at building a prototype for an integrated system of methods, models,and techniques with mine complex fields modeled digitally and represented visually. Specifically, the paper addressed the issues of data mining and knowledge discovery techniques as used in the processing of geological and ore deposit samples, digital modeling techniques as used in the description of mine complex fields, 3D visual simulation techniques as used in the representation of ore bodies and underground excavations, seamless interfacing techniques with other systems such as CAD and web GIS as used in the restructuring of 2D data into 3D models and mapping of 3D models onto 2D graphics, and implementation techniques as used in the case of building a web based prototype system for the integrated modeling and visualization of underground mines.
A 3D Babcock-Leighton Solar Dynamo Model
Miesch, Mark S
2014-01-01
We present a 3D kinematic solar dynamo model in which poloidal field is generated by the emergence and dispersal of tilted sunspot pairs (more generally Bipolar Magnetic Regions, or BMRs). The axisymmetric component of this model functions similarly to previous 2D Babcock-Leighton (BL) dynamo models that employ a double-ring prescription for poloidal field generation but we generalize this prescription into a 3D flux emergence algorithm that places BMRs on the surface in response to the dynamo-generated toroidal field. In this way, the model can be regarded as a unification of BL dynamo models (2D in radius/latitude) and surface flux transport models (2D in latitude/longitude) into a more self-consistent framework that captures the full 3D structure of the evolving magnetic field. The model reproduces some basic features of the solar cycle including an 11-yr periodicity, equatorward migration of toroidal flux in the deep convection zone, and poleward propagation of poloidal flux at the surface. The poleward-p...
Mock, Samuel; Allenbach, Robin; Reynolds, Lance; Wehrens, Philip; Kurmann-Matzenauer, Eva; Kuhn, Pascal; Michael, Salomè; Di Tommaso, Gennaro; Herwegh, Marco
2016-04-01
The Swiss Molasse Basin comprises the western and central part of the North Alpine Foreland Basin. In recent years it has come under closer scrutiny due to its promising geopotentials such as geothermal energy and CO2 sequestration. In order to adress these topics good knowledge of the subsurface is a key prerequisite. For that matter, geological 3D models serve as valuable tools. In collaboration with the Swiss Geological Survey (swisstopo) and as part of the project GeoMol CH, a geological 3D model of the Swiss Molasse Basin in the Canton of Bern has been built. The model covers an area of 1810 km2and reaches depth of up to 6.7 km. It comprises 10 major Cenozoic and Mesozoic units and numerous faults. The 3D model is mainly based on 2D seismic data complemented by information from few deep wells. Additionally, data from geological maps and profiles were used for refinement at shallow depths. In total, 1163 km of reflection seismic data, along 77 seismic lines, have been interpreted by different authors with respect to stratigraphy and structures. Both, horizons and faults, have been interpreted in 2D and modelled in 3D using IHS's Kingdom Suite and Midland Valley's MOVE software packages, respectively. Given the variable degree of subsurface information available, each 3D model is subject of uncertainty. With the primary input data coming from interpretation of reflection seismic data, a variety of uncertainties comes into play. Some of them are difficult to address (e.g. author's style of interpretation) while others can be quantified (e.g. mis-tie correction, well-tie). An important source of uncertainties is the quality of seismic data; this affects the traceability and lateral continuation of seismic reflectors. By defining quality classes we can semi-quantify this source of uncertainty. In order to visualize the quality and density of the input data in a meaningful way, we introduce quality-weighted data density maps. In combination with the geological 3D
Building Statistical Shape Spaces for 3D Human Modeling
Pishchulin, Leonid; Wuhrer, Stefanie; Helten, Thomas; Theobalt, Christian; Schiele, Bernt
2015-01-01
Statistical models of 3D human shape and pose learned from scan databases have developed into valuable tools to solve a variety of vision and graphics problems. Unfortunately, most publicly available models are of limited expressiveness as they were learned on very small databases that hardly reflect the true variety in human body shapes. In this paper, we contribute by rebuilding a widely used statistical body representation from the largest commercially available scan database, and making t...
Geometric and Colour Data Fusion for Outdoor 3D Models
Ricardo Chacón
2012-05-01
Full Text Available This paper deals with the generation of accurate, dense and coloured 3D models of outdoor scenarios from scanners. This is a challenging research field in which several problems still remain unsolved. In particular, the process of 3D model creation in outdoor scenes may be inefficient if the scene is digitalized under unsuitable technical (specific scanner on-board camera and environmental (rain, dampness, changing illumination conditions. We address our research towards the integration of images and range data to produce photorealistic models. Our proposal is based on decoupling the colour integration and geometry reconstruction stages, making them independent and controlled processes. This issue is approached from two different viewpoints. On the one hand, given a complete model (geometry plus texture, we propose a method to modify the original texture provided by the scanner on-board camera with the colour information extracted from external images taken at given moments and under specific environmental conditions. On the other hand, we propose an algorithm to directly assign external images onto the complete geometric model, thus avoiding tedious on-line calibration processes. We present the work conducted on two large Roman archaeological sites dating from the first century A.D., namely, the Theatre of Segobriga and the Fori Porticus of Emerita Augusta, both in Spain. The results obtained demonstrate that our approach could be useful in the digitalization and 3D modelling fields.
Towards a 3d Spatial Urban Energy Modelling Approach
Bahu, J.-M.; Koch, A.; Kremers, E.; Murshed, S. M.
2013-09-01
Today's needs to reduce the environmental impact of energy use impose dramatic changes for energy infrastructure and existing demand patterns (e.g. buildings) corresponding to their specific context. In addition, future energy systems are expected to integrate a considerable share of fluctuating power sources and equally a high share of distributed generation of electricity. Energy system models capable of describing such future systems and allowing the simulation of the impact of these developments thus require a spatial representation in order to reflect the local context and the boundary conditions. This paper describes two recent research approaches developed at EIFER in the fields of (a) geo-localised simulation of heat energy demand in cities based on 3D morphological data and (b) spatially explicit Agent-Based Models (ABM) for the simulation of smart grids. 3D city models were used to assess solar potential and heat energy demand of residential buildings which enable cities to target the building refurbishment potentials. Distributed energy systems require innovative modelling techniques where individual components are represented and can interact. With this approach, several smart grid demonstrators were simulated, where heterogeneous models are spatially represented. Coupling 3D geodata with energy system ABMs holds different advantages for both approaches. On one hand, energy system models can be enhanced with high resolution data from 3D city models and their semantic relations. Furthermore, they allow for spatial analysis and visualisation of the results, with emphasis on spatially and structurally correlations among the different layers (e.g. infrastructure, buildings, administrative zones) to provide an integrated approach. On the other hand, 3D models can benefit from more detailed system description of energy infrastructure, representing dynamic phenomena and high resolution models for energy use at component level. The proposed modelling strategies
Technical illustration based on 3D CSG models
GENG Wei-dong; DING Lei; YU Hong-feng; PAN Yun-he
2005-01-01
This paper presents an automatic non-photorealistic rendering approach to generating technical illustration from 3D models. It first decomposes the 3D object into a set of CSG primitives, and then performs the hidden surface removal based on the prioritized list, in which the rendition order of CSG primitives is sorted out by depth. Then, each primitive is illustrated by the pre-defined empirical lighting model, and the system mimics the stroke-drawing by user-specified style. In order to artistically and flexibly modulate the illumination, the empirical lighting model is defined by three major components: parameters of multi-level lighting intensities, parametric spatial occupations for each lighting level, and an interpolation method to calculate the lighting units into the spatial occupation of CSG primitives, instead of"pixel-by-pixel" painting. This region-by-region shading facilitates the simulation of illustration styles.
3D Babcock-Leighton Solar Dynamo Models
Miesch, Mark S.; Hazra, Gopal; Karak, Bidya Binay; Teweldebirhan, Kinfe; Upton, Lisa
2016-05-01
We present results from the new STABLE (Surface flux Transport and Babcock Leighton) Dynamo Model. STABLE is a 3D Babcock-Leighton/Flux Transport dynamo model in which the source of poloidal field is the explicit emergence, distortion, and dispersal of bipolar magnetic regions (BMRs). In this talk I will discuss initial results with axisymmetric flow fields, focusing on the operation of the model, the general features of the cyclic solutions, and the challenge of achieving supercritical dynamo solutions using only the Babcock-Leighton source term. Then I will present dynamo simulations that include 3D convective flow fields based on the observed velocity power spectrum inferred from photospheric Dopplergrams. I'll use these simulations to assess how the explicit transport and amplification of fields by surface convection influences the operation of the dynamo. I will also discuss the role of surface magnetic fields in regulating the subsurface toroidal flux budget.
3-D model-based tracking for UAV indoor localization.
Teulière, Céline; Marchand, Eric; Eck, Laurent
2015-05-01
This paper proposes a novel model-based tracking approach for 3-D localization. One main difficulty of standard model-based approach lies in the presence of low-level ambiguities between different edges. In this paper, given a 3-D model of the edges of the environment, we derive a multiple hypotheses tracker which retrieves the potential poses of the camera from the observations in the image. We also show how these candidate poses can be integrated into a particle filtering framework to guide the particle set toward the peaks of the distribution. Motivated by the UAV indoor localization problem where GPS signal is not available, we validate the algorithm on real image sequences from UAV flights. PMID:25099967
Engineering cancer microenvironments for in vitro 3-D tumor models
Waseem Asghar
2015-12-01
Full Text Available The natural microenvironment of tumors is composed of extracellular matrix (ECM, blood vasculature, and supporting stromal cells. The physical characteristics of ECM as well as the cellular components play a vital role in controlling cancer cell proliferation, apoptosis, metabolism, and differentiation. To mimic the tumor microenvironment outside the human body for drug testing, two-dimensional (2-D and murine tumor models are routinely used. Although these conventional approaches are employed in preclinical studies, they still present challenges. For example, murine tumor models are expensive and difficult to adopt for routine drug screening. On the other hand, 2-D in vitro models are simple to perform, but they do not recapitulate natural tumor microenvironment, because they do not capture important three-dimensional (3-D cell–cell, cell–matrix signaling pathways, and multi-cellular heterogeneous components of the tumor microenvironment such as stromal and immune cells. The three-dimensional (3-D in vitro tumor models aim to closely mimic cancer microenvironments and have emerged as an alternative to routinely used methods for drug screening. Herein, we review recent advances in 3-D tumor model generation and highlight directions for future applications in drug testing.
GPU-accelerated 3-D model-based tracking
Model-based approaches to tracking the pose of a 3-D object in video are effective but computationally demanding. While statistical estimation techniques, such as the particle filter, are often employed to minimize the search space, real-time performance remains unachievable on current generation CPUs. Recent advances in graphics processing units (GPUs) have brought massively parallel computational power to the desktop environment and powerful developer tools, such as NVIDIA Compute Unified Device Architecture (CUDA), have provided programmers with a mechanism to exploit it. NVIDIA GPUs' single-instruction multiple-thread (SIMT) programming model is well-suited to many computer vision tasks, particularly model-based tracking, which requires several hundred 3-D model poses to be dynamically configured, rendered, and evaluated against each frame in the video sequence. Using 6 degree-of-freedom (DOF) rigid hand tracking as an example application, this work harnesses consumer-grade GPUs to achieve real-time, 3-D model-based, markerless object tracking in monocular video.
A 3D alcoholic liver disease model on a chip.
Lee, JaeSeo; Choi, BongHwan; No, Da Yoon; Lee, GeonHui; Lee, Seung-Ri; Oh, HyunJik; Lee, Sang-Hoon
2016-03-14
Alcohol is one of the main causes of liver diseases, and the development of alcoholic liver disease (ALD) treatment methods has been one of the hottest issues. For this purpose, development of in vitro models mimicking the in vivo physiology is one of the critical requirements, and they help to determine the disease mechanisms and to discover the treatment method. Herein, a three-dimensional (3D) ALD model was developed and its superior features in mimicking the in vivo condition were demonstrated. A spheroid-based microfluidic chip was employed for the development of the 3D in vitro model of ALD progression. We co-cultured rat primary hepatocytes and hepatic stellate cells (HSCs) in a fluidic chip to investigate the role of HSCs in the recovery of liver with ALD. An interstitial level of flow derived by an osmotic pump was applied to the chip to provide in vivo mimicking of fluid activity. Using this in vitro tool, we were able to observe structural changes and decreased hepatic functions with the increase in ethanol concentration. The recovery process of liver injured by alcohol was observed by providing fresh culture medium to the damaged 3D liver tissue for few days. A reversibly- and irreversibly-injured ALD model was established. The proposed model can not only be used for the research of alcoholic disease mechanism, but also has the potential for use in studies of hepatotoxicity and drug screening applications. PMID:26857817
3D modeling of dual-gate FinFET.
Mil'shtein, Samson; Devarakonda, Lalitha; Zanchi, Brian; Palma, John
2012-01-01
The tendency to have better control of the flow of electrons in a channel of field-effect transistors (FETs) did lead to the design of two gates in junction field-effect transistors, field plates in a variety of metal semiconductor field-effect transistors and high electron mobility transistors, and finally a gate wrapping around three sides of a narrow fin-shaped channel in a FinFET. With the enhanced control, performance trends of all FETs are still challenged by carrier mobility dependence on the strengths of the electrical field along the channel. However, in cases when the ratio of FinFET volume to its surface dramatically decreases, one should carefully consider the surface boundary conditions of the device. Moreover, the inherent non-planar nature of a FinFET demands 3D modeling for accurate analysis of the device performance. Using the Silvaco modeling tool with quantization effects, we modeled a physical FinFET described in the work of Hisamoto et al. (IEEE Tran. Elec. Devices 47:12, 2000) in 3D. We compared it with a 2D model of the same device. We demonstrated that 3D modeling produces more accurate results. As 3D modeling results came close to experimental measurements, we made the next step of the study by designing a dual-gate FinFET biased at Vg1 >Vg2. It is shown that the dual-gate FinFET carries higher transconductance than the single-gate device. PMID:23148493
Error Analysis Of 3d Polygonal Model:A Survey
Devendra Singh Rajput
2012-05-01
Full Text Available Various applications of computer graphics, (like animation, scientific visualization, and virtual reality involve the manipulation of geometric models. They are generally represented by triangular meshes due to its wide acceptance to process on rendering systems. The need of realism and high visual fidelity and the latest advances on scanning devices has increased complexity and size of triangular meshes. The original 3D model gets modified because of activities like approximation, transmission, processing and storage etc. Mostly the modification occurs due to simplification approaches which primarily use geometric distance metric as their simplification criteria. But it is hard to measure a small distance error accurately whereas other geometric or appearance error (like high curvature, thin region, color, texture, normals and volumetric has greater importance. Hence it is essential to understand the applicability of various parameters to evaluate the quality of 3D model. This paper briefly surveys the various errors analysis techniques, error metrics and tools to assess the quality of 3D mesh models.
CityGML - Interoperable semantic 3D city models
Gröger, Gerhard; Plümer, Lutz
2012-07-01
CityGML is the international standard of the Open Geospatial Consortium (OGC) for the representation and exchange of 3D city models. It defines the three-dimensional geometry, topology, semantics and appearance of the most relevant topographic objects in urban or regional contexts. These definitions are provided in different, well-defined Levels-of-Detail (multiresolution model). The focus of CityGML is on the semantical aspects of 3D city models, its structures, taxonomies and aggregations, allowing users to employ virtual 3D city models for advanced analysis and visualization tasks in a variety of application domains such as urban planning, indoor/outdoor pedestrian navigation, environmental simulations, cultural heritage, or facility management. This is in contrast to purely geometrical/graphical models such as KML, VRML, or X3D, which do not provide sufficient semantics. CityGML is based on the Geography Markup Language (GML), which provides a standardized geometry model. Due to this model and its well-defined semantics and structures, CityGML facilitates interoperable data exchange in the context of geo web services and spatial data infrastructures. Since its standardization in 2008, CityGML has become used on a worldwide scale: tools from notable companies in the geospatial field provide CityGML interfaces. Many applications and projects use this standard. CityGML is also having a strong impact on science: numerous approaches use CityGML, particularly its semantics, for disaster management, emergency responses, or energy-related applications as well as for visualizations, or they contribute to CityGML, improving its consistency and validity, or use CityGML, particularly its different Levels-of-Detail, as a source or target for generalizations. This paper gives an overview of CityGML, its underlying concepts, its Levels-of-Detail, how to extend it, its applications, its likely future development, and the role it plays in scientific research. Furthermore, its
3D fracture permeability modelling in offshore Arabian Gulf reservoir
Bushara, M.N.; El Tawel, A.; Borougha, H.; Dabbouk, C. [Zakum Development Co., Abu Dhabi (United Arab Emirates); Daly, C. [Roxar Ltd., Dubai (United Arab Emirates)
2001-06-01
A stochastic method has been developed to predict fracture permeability distribution for oil fields. This new method does a better job than current methods in determining water encroachment trends. The method was developed based on a study conducted on a carbonate reservoir located offshore Abu Dhabi. The 3D model allows petroleum engineers to assess fractures and to better understand their geologic control in terms of permeability in reservoirs with single porosity models. In this study, strain field over the reservoir, which correlated with test permeability, was obtained from curvature analysis and calibrated to strain calculated from core fractures. Curvature analysis included some uncertainties such as strain estimates, details of fracture spatial geometry and shear/strike-slip movements. It was concluded that these uncertainties could be eliminated with better strain field determination and 3D seismic data. 4 refs., 5 figs.
3D root canal modeling for advanced endodontic treatment
Hong, Shane Y.; Dong, Janet
2002-06-01
More than 14 million teeth receive endodontic (root canal) treatment annually. Before a clinician's inspection and diagnosis, destructive access preparation by removing teeth crown and dentin is usually needed. This paper presents a non-invasive method for accessing internal tooth geometry by building 3-D tooth model from 2-D radiographic and endoscopic images to be used for an automatic prescription system of computer-aided treatment procedure planning, and for the root canal preparation by an intelligent micro drilling machine with on-line monitoring. It covers the techniques specific for dental application in the radiographic images acquirement, image enhancement, image segmentation and feature recognition, distance measurement and calibration, merging 2D image into 3D mathematical model representation and display. Included also are the methods to form references for irregular teeth geometry and to do accurately measurement with self-calibration.
Modeling 2D and 3D Horizontal Wells Using CVFA
Chen, Zhangxin; Huan, Guanren; Li, Baoyan
2003-01-01
In this paper we present an application of the recently developed control volume function approximation (CVFA) method to the modeling and simulation of 2D and 3D horizontal wells in petroleum reservoirs. The base grid for this method is based on a Voronoi grid. One of the features of the CVFA is that the flux at the interfaces of control volumes can be accurately computed via function approximations. Also, it reduces grid orientation effects and applies to any shape of eleme...
Study of 3D-modelling software environments
Егорова, Ирина Николаевна; Гайдамащук, Алиса Владимировна
2013-01-01
The study of three-dimensional modeling software packages such as Autodesk Maya, Autodesk 3Ds Studio Max, Lightwave 3D, Maxon Cinema 4D, Blender, ZBrush was conducted in the paper. The analysis of software packages allowed to identify the most effective ones. These were Autodesk Maya, Autodesk 3Ds Studio Max and ZBrush packages. The selected software packages were used for the creation of a computer scene, the main elements of which are interior, character and animation. Practical research al...
Camera Calibration by Registration Stereo Reconstruction to 3D Model
Klečka, J.
2015-01-01
Paper aims at unusual way to camera calibration. The main idea is that by registration of uncalibrated stereo reconstruction to 3D model of the same scene is eliminated ambiguity of the reconstruction. The reason for this is that exact metric scene reconstruction from image pair can be understate as information equivalent to calibration of the source camera pair. Described principles were verified by experiment on real data and results are presented at the end of the paper.
Registration of 3D Face Scans with Average Face Models
Salah, Albert Ali; Alyuz, N.; Akarun, L.
2008-01-01
The accuracy of a 3D face recognition system depends on a correct registration that aligns the facial surfaces and makes a comparison possible. The best results obtained so far use a costly one-to-all registration approach, which requires the registration of each facial surface to all faces in the gallery. We explore the approach of registering the new facial surface to an average face model (AFM), which automatically establishes correspondence to the pre-registered gallery faces. We propose ...
PIXIE3D: An efficient, fully implicit, parallel, 3D extended MHD code for fusion plasma modeling
PIXIE3D is a modern, parallel, state-of-the-art extended MHD code that employs fully implicit methods for efficiency and accuracy. It features a general geometry formulation, and is therefore suitable for the study of many magnetic fusion configurations of interest. PIXIE3D advances the state of the art in extended MHD modeling in two fundamental ways. Firstly, it employs a novel conservative finite volume scheme which is remarkably robust and stable, and demands very small physical and/or numerical dissipation. This is a fundamental requirement when one wants to study fusion plasmas with realistic conductivities. Secondly, PIXIE3D features fully-implicit time stepping, employing Newton-Krylov methods for inverting the associated nonlinear systems. These methods have been shown to be scalable and efficient when preconditioned properly. Novel preconditioned ideas (so-called physics based), which were prototypes in the context of reduced MHD, have been adapted for 3D primitive-variable resistive MHD in PIXIE3D, and are currently being extended to Hall MHD. PIXIE3D is fully parallel, employing PETSc for parallelism. PIXIE3D has been thoroughly benchmarked against linear theory and against other available extended MHD codes on nonlinear test problems (such as the GEM reconnection challenge). We are currently in the process of extending such comparisons to fusion-relevant problems in realistic geometries. In this talk, we will describe both the spatial discretization approach and the preconditioning strategy employed for extended MHD in PIXIE3D. We will report on recent benchmarking studies between PIXIE3D and other 3D extended MHD codes, and will demonstrate its usefulness in a variety of fusion-relevant configurations such as Tokamaks and Reversed Field Pinches. (Author)