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Auswahl der wissenschaftlichen Literatur zum Thema „Kilometer-scale model“
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Zeitschriftenartikel zum Thema "Kilometer-scale model"
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Schär, Christoph, Oliver Fuhrer, Andrea Arteaga, Nikolina Ban, Christophe Charpilloz, Salvatore Di Girolamo, Laureline Hentgen et al. „Kilometer-Scale Climate Models: Prospects and Challenges“. Bulletin of the American Meteorological Society 101, Nr. 5 (01.05.2020): E567—E587. http://dx.doi.org/10.1175/bams-d-18-0167.1.
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Abstract Currently major efforts are underway toward refining the horizontal resolution (or grid spacing) of climate models to about 1 km, using both global and regional climate models (GCMs and RCMs). Several groups have succeeded in conducting kilometer-scale multiweek GCM simulations and decadelong continental-scale RCM simulations. There is the well-founded hope that this increase in resolution represents a quantum jump in climate modeling, as it enables replacing the parameterization of moist convection by an explicit treatment. It is expected that this will improve the simulation of the water cycle and extreme events and reduce uncertainties in climate change projections. While kilometer-scale resolution is commonly employed in limited-area numerical weather prediction, enabling it on global scales for extended climate simulations requires a concerted effort. In this paper, we exploit an RCM that runs entirely on graphics processing units (GPUs) and show examples that highlight the prospects of this approach. A particular challenge addressed in this paper relates to the growth in output volumes. It is argued that the data avalanche of high-resolution simulations will make it impractical or impossible to store the data. Rather, repeating the simulation and conducting online analysis will become more efficient. A prototype of this methodology is presented. It makes use of a bit-reproducible model version that ensures reproducible simulations across hardware architectures, in conjunction with a data virtualization layer as a common interface for output analyses. An assessment of the potential of these novel approaches will be provided.
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Ban, Nikolina, Cécile Caillaud, Erika Coppola, Emanuela Pichelli, Stefan Sobolowski, Marianna Adinolfi, Bodo Ahrens et al. „The first multi-model ensemble of regional climate simulations at kilometer-scale resolution, part I: evaluation of precipitation“. Climate Dynamics 57, Nr. 1-2 (09.04.2021): 275–302. http://dx.doi.org/10.1007/s00382-021-05708-w.
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AbstractHere we present the first multi-model ensemble of regional climate simulations at kilometer-scale horizontal grid spacing over a decade long period. A total of 23 simulations run with a horizontal grid spacing of $$\sim $$ ∼ 3 km, driven by ERA-Interim reanalysis, and performed by 22 European research groups are analysed. Six different regional climate models (RCMs) are represented in the ensemble. The simulations are compared against available high-resolution precipitation observations and coarse resolution ($$\sim $$ ∼ 12 km) RCMs with parameterized convection. The model simulations and observations are compared with respect to mean precipitation, precipitation intensity and frequency, and heavy precipitation on daily and hourly timescales in different seasons. The results show that kilometer-scale models produce a more realistic representation of precipitation than the coarse resolution RCMs. The most significant improvements are found for heavy precipitation and precipitation frequency on both daily and hourly time scales in the summer season. In general, kilometer-scale models tend to produce more intense precipitation and reduced wet-hour frequency compared to coarse resolution models. On average, the multi-model mean shows a reduction of bias from $$\sim \,$$ ∼ −40% at 12 km to $$\sim \,$$ ∼ −3% at 3 km for heavy hourly precipitation in summer. Furthermore, the uncertainty ranges i.e. the variability between the models for wet hour frequency is reduced by half with the use of kilometer-scale models. Although differences between the model simulations at the kilometer-scale and observations still exist, it is evident that these simulations are superior to the coarse-resolution RCM simulations in the representing precipitation in the present-day climate, and thus offer a promising way forward for investigations of climate and climate change at local to regional scales.
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Mittermaier, M. P., und G. Csima. „Ensemble versus Deterministic Performance at the Kilometer Scale“. Weather and Forecasting 32, Nr. 5 (15.09.2017): 1697–709. http://dx.doi.org/10.1175/waf-d-16-0164.1.
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Abstract What is the benefit of a near-convection-resolving ensemble over a near-convection-resolving deterministic forecast? In this paper, a way in which ensemble and deterministic numerical weather prediction (NWP) systems can be compared is demonstrated using a probabilistic verification framework. Three years’ worth of raw forecasts from the Met Office Unified Model (UM) 12-member 2.2-km Met Office Global and Regional Ensemble Prediction System (MOGREPS-UK) ensemble and 1.5-km Met Office U.K. variable resolution (UKV) deterministic configuration were compared, utilizing a range of forecast neighborhood sizes centered on surface synoptic observing site locations. Six surface variables were evaluated: temperature, 10-m wind speed, visibility, cloud-base height, total cloud amount, and hourly precipitation. Deterministic forecasts benefit more from the application of neighborhoods, though ensemble forecast skill can also be improved. This confirms that while neighborhoods can enhance skill by sampling more of the forecast, a single deterministic model state in time cannot provide the variability, especially at the kilometer scale, where rapid error growth acts to limit local predictability. Ensembles are able to account for the uncertainty at larger, synoptic scales. The results also show that the rate of decrease in skill with lead time is greater for the deterministic UKV. MOGREPS-UK retains higher skill for longer. The concept of a skill differential is introduced to find the smallest neighborhood size at which the deterministic and ensemble scores are comparable. This was found to be 3 × 3 (6.6 km) for MOGREPS-UK and 11 × 11 (16.5 km) for UKV. Comparable scores are between 2% and 40% higher for MOGREPS-UK, depending on the variable. Naively, this would also suggest that an extra 10 km in spatial accuracy is gained by using a kilometer-scale ensemble.
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Zeman, Christian, Nils P. Wedi, Peter D. Dueben, Nikolina Ban und Christoph Schär. „Model intercomparison of COSMO 5.0 and IFS 45r1 at kilometer-scale grid spacing“. Geoscientific Model Development 14, Nr. 7 (27.07.2021): 4617–39. http://dx.doi.org/10.5194/gmd-14-4617-2021.
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Abstract. The increase in computing power and recent model developments allow for the use of global kilometer-scale weather and climate models for routine forecasts. At these scales, deep convective processes can be partially resolved explicitly by the model dynamics. Next to horizontal resolution, other aspects such as the applied numerical methods, the use of the hydrostatic approximation, and time step size are factors that might influence a model's ability to resolve deep convective processes. In order to improve our understanding of the role of these factors, a model intercomparison between the nonhydrostatic COSMO model and the hydrostatic Integrated Forecast System (IFS) from ECMWF has been conducted. Both models have been run with different spatial and temporal resolutions in order to simulate 2 summer days over Europe with strong convection. The results are analyzed with a focus on vertical wind speed and precipitation. Results show that even at around 3 km horizontal grid spacing the effect of the hydrostatic approximation seems to be negligible. However, time step proves to be an important factor for deep convective processes, with a reduced time step generally allowing for higher updraft velocities and thus more energy in vertical velocity spectra, in particular for shorter wavelengths. A shorter time step is also causing an earlier onset and peak of the diurnal cycle. Furthermore, the amount of horizontal diffusion plays a crucial role for deep convection with more diffusion generally leading to larger convective cells and higher precipitation intensities. The study also shows that for both models the parameterization of deep convection leads to lower updraft and precipitation intensities and biases in the diurnal cycle with a precipitation peak which is too early.
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Pay, M. T., F. Martínez, M. Guevara und J. M. Baldasano. „Air quality forecasts at kilometer scale grid over Spanish complex terrains“. Geoscientific Model Development Discussions 7, Nr. 2 (09.04.2014): 2293–334. http://dx.doi.org/10.5194/gmdd-7-2293-2014.
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Abstract. CALIOPE-AQFS represents the current state-of-the-art in air quality forecasting systems running at high resolution over high performance computing platforms. It provides 48 h forecast of main pollutants over Spain at 4 km horizontal resolution, and over the most populated areas with complex terrains in Spain (Barcelona, Madrid and Andalucia domains) at 1 km. Increased horizontal resolution from 4 km to 1 km over the aforementioned domains leads to finer texture and more realistic concentration maps, justified by the increase of NO2/O3 spatial correlation coefficients from 0.79/0.69 (4 km) to 0.81/0.73 (1 km). High resolution emissions using the bottom-up HERMESv2.0 model are essential to improve the model performance when increasing resolution at urban scale, but it is not sufficient. Decreasing grid spacing does not reveal the expected improvement on hourly statistics, decreasing NO2 bias only in ~ 2 μg m−3 and increasing O3 bias in ~ 1 μg m−3. The grid effect is less pronounced for PM10 because part of its mass consists of secondary aerosols which are less affected by a decreasing grid size in contrast to the locally emitted primary components. The resolution increase has the highest impact over Barcelona, where air flow is mainly controlled by mesoscale phenomena and a lower PBL. Despite the merits and potential uses of the 1 km simulation, the limitations of current model formulations do not allow confirming their expected superiority close to highly urbanized areas and large sources. Future work should combine high grid resolution with techniques that decrease subgrid variability and models that consider urban morphology and thermal parameters.
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Bauville, Arthur, und Stefan M. Schmalholz. „Thermo-mechanical model for the finite strain gradient in kilometer-scale shear zones“. Geology 41, Nr. 5 (Mai 2013): 567–70. http://dx.doi.org/10.1130/g33953.1.
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Pay, M. T., F. Martínez, M. Guevara und J. M. Baldasano. „Air quality forecasts on a kilometer-scale grid over complex Spanish terrains“. Geoscientific Model Development 7, Nr. 5 (08.09.2014): 1979–99. http://dx.doi.org/10.5194/gmd-7-1979-2014.
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Abstract. The CALIOPE Air Quality Forecast System (CALIOPE-AQFS) represents the current state of the art in air quality forecasting systems of high-resolution running on high-performance computing platforms. It provides a 48 h forecast of NO2, O3, SO2, PM10, PM2.5, CO, and C6H6 at a 4 km horizontal resolution over all of Spain, and at a 1 km horizontal resolution over the most populated areas in Spain with complex terrains (the Barcelona (BCN), Madrid (MAD) and Andalusia (AND) domains). Increased horizontal resolution from 4 to 1 km over the aforementioned domains leads to finer textures and more realistic concentration maps, which is justified by the increase in NO2/O3 spatial correlation coefficients from 0.79/0.69 (4 km) to 0.81/0.73 (1 km). High-resolution emissions using the bottom-up HERMESv2.0 model are essential for improving model performance when increasing resolution on an urban scale, but it is still insufficient. Decreasing grid spacing does not reveal the expected improvement in hourly statistics, i.e., decreasing NO2 bias by only ~ 2 μg m−3 and increasing O3 bias by ~ 1 μg m−3. The grid effect is less pronounced for PM10, because part of its mass consists of secondary aerosols, which are less affected than the locally emitted primary components by a decreasing grid size. The resolution increase has the highest impact over Barcelona, where air flow is controlled mainly by mesoscale phenomena and a lower planetary boundary layer (PBL). Despite the merits and potential uses of the 1-km simulation, the limitations of current model formulations do not allow confirmation of their expected superiority close to highly urbanized areas and large emissions sources. Future work should combine high grid resolutions with techniques that decrease subgrid variability (e.g., stochastic field methods), and also include models that consider urban morphology and thermal parameters.
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Idier, Déborah, Albert Falqués, Jérémy Rohmer und Jaime Arriaga. „Self-organized kilometer-scale shoreline sand wave generation: Sensitivity to model and physical parameters“. Journal of Geophysical Research: Earth Surface 122, Nr. 9 (September 2017): 1678–97. http://dx.doi.org/10.1002/2017jf004197.
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Xia, Ming. „An upscale theory of thermal-mechanical coupling particle simulation for non-isothermal problems in two-dimensional quasi-static system“. Engineering Computations 32, Nr. 7 (05.10.2015): 2136–65. http://dx.doi.org/10.1108/ec-04-2014-0076.
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Purpose – The purpose of this paper is to present an upscale theory of the thermal-mechanical coupling particle simulation for non-isothermal problems in two-dimensional quasi-static system, under which a small length-scale particle model can exactly reproduce the same mechanical and thermal results with that of a large length-scale one. Design/methodology/approach – The objective is achieved by extending the upscale theory of particle simulation for two-dimensional quasi-static problems from an isothermal system to a non-isothermal one. Findings – Five similarity criteria, namely geometric, material (mechanical and thermal) properties, gravity acceleration, (mechanical and thermal) time steps, thermal initial and boundary conditions (Dirichlet/Neumann boundary conditions), under which a small-length-scale particle model can exactly reproduce both the mechanical and thermal behavior with that of a large length-scale model for non-isothermal problems in a two-dimensional quasi-static system are proposed. Furthermore, to test the proposed upscale theory, two typical examples subjected to different thermal boundary conditions are simulated using two particle models of different length scale. Originality/value – The paper provides some important theoretical guidances to modeling thermal-mechanical coupled problems at both the engineering length scale (i.e. the meter scale) and the geological length scale (i.e. the kilometer scale) using the particle simulation method directly. The related simulation results from two typical examples of significantly different length scales (i.e. a meter scale and a kilometer scale) have demonstrated the usefulness and correctness of the proposed upscale theory for simulating non-isothermal problems in two-dimensional quasi-static system.
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Muñoz-Esparza, Domingo, Robert D. Sharman und Stanley B. Trier. „On the Consequences of PBL Scheme Diffusion on UTLS Wave and Turbulence Representation in High-Resolution NWP Models“. Monthly Weather Review 148, Nr. 10 (01.10.2020): 4247–65. http://dx.doi.org/10.1175/mwr-d-20-0102.1.
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AbstractMesoscale numerical weather prediction (NWP) models are routinely exercised at kilometer-scale horizontal grid spacings (Δx). Such fine grids will usually allow at least partial resolution of small-scale gravity waves and turbulence in the upper troposphere and lower stratosphere (UTLS). However, planetary boundary layer (PBL) parameterization schemes used with these NWP model simulations typically apply explicit subgrid-scale vertical diffusion throughout the entire vertical extent of the domain, an effect that cannot be ignored. By way of an example case of observed widespread turbulence over the U.S. Great Plains, we demonstrate that the PBL scheme’s mixing in NWP model simulations of Δx = 1 km can have significant effects on the onset and characteristics of the modeled UTLS gravity waves. Qualitatively, PBL scheme diffusion is found to affect not only background conditions responsible for UTLS wave activity, but also to control the local vertical mixing that triggers or hinders the onset and propagation of these waves. Comparisons are made to a reference large-eddy simulation with Δx = 250 m to statistically quantify these effects. A significant and systematic overestimation of resolved vertical velocities, wave-scale fluxes, and kinetic energy is uncovered in the 1-km simulations, both in clear-air and in-cloud conditions. These findings are especially relevant for upper-level gravity wave and turbulence simulations using high-resolution kilometer-scale NWP models.
Dissertationen zum Thema "Kilometer-scale model"
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Kretzschmar, Jan. „Improving the representation of Arctic clouds in atmospheric models across scales using observations“. 2021. https://ul.qucosa.de/id/qucosa%3A75240.
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With a nearly twice as strongly pronounced temperature increase compared to that of the Northern Hemisphere, the Arctic is especially susceptible to global climate change. The effect of clouds on the Arctic warming is especially uncertain, which is caused by misrepresented cloud microphysical processes in atmospheric models. This thesis aims at employing a scale- and definition-aware comparison of models and observations and will propose changes how to better parameterize Arctic clouds in atmospheric models.
In the first part of this thesis, ECHAM6, which is the atmospheric component of the MPI-ESM global climate model, is compared to spaceborne lidar observations of clouds from the CALIPSO satellite. This comparison shows that ECHAM6 overestimates Arctic low-level, liquid containing clouds over snow- and ice-covered surfaces, which consequently leads to an overestimated amount of radiative energy received by the surface. Using sensitivity studies, it is shown that the probable cause of the model biases in cloud amount and phase is related to misrepresented cloud microphysical parameterization (i.e., parameterization of the Wegener-Bergeron-Findeisen process and of the cloud cover scheme) in ECHAM6. By revising those processes, a better representation of cloud amount and cloud phase is achieved, which helps to more accurately simulated the amount of radiative energy received by the Arctic in ECHAM6.
The second part of this thesis will focus on a comparison of kilometer-scale simulation with the ICON model to aircraft observations from the ACLOUD campaign that took place in May/June 2017 over the sea ice-covered Arctic Ocean north of Svalbard, Norway. By comparing measurements of solar and terrestrial surface irradiances during ACLOUD flights to the respective quantities in ICON, it is shown that the model systematically overestimates the transmissivity of the mostly liquid clouds during the campaign. This model bias is traced back to the way cloud condensation nuclei get activated into cloud droplets in the two-moment, bulk microphysical scheme used. By parameterizing subgrid-scale vertical motion as a function of turbulent kinetic energy, a more realistic CCN activation into cloud droplets is achieved. This consequently results in an improved representation of cloud optical properties in the ICON simulations.
Furthermore, the results of two studies to which contributions have been made during the Ph.D. will be summarized. In Petersik et al. 2018, the impact of subgrid-scale variability in clear-sky relative humidity on hygroscopic growth of aerosols in the aerosol-climate model ECHAM6-HAM2 has been explored. It was shown that the revised parameterization of hygroscopic growth of aerosols resulted in a stronger swelling of aerosol particles, which consequently causes an increased backscattering of solar radiation. In the study of Costa-Suros et al. 2019, it is explored whether it is possible to detect and attribute aerosol-cloud interactions in large-eddy simulation over Germany. It was shown that an increase in cloud droplet number concentration could be attributed to an increased aerosol load, while such an attribution was not possible for other cloud micro- and macrophysical variables.
Buchteile zum Thema "Kilometer-scale model"
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„Conservation, Ecology, and Management of Catfish: The Second International Symposium“. In Conservation, Ecology, and Management of Catfish: The Second International Symposium, herausgegeben von SARA J. TRIPP, MICHAEL J. HILL, HEATHER A. CALKINS, RONALD C. BROOKS, DAVID P. HERZOG, DAVID E. OSTENDORF, ROBERT A. HRABIK und JAMES E. GARVEY. American Fisheries Society, 2011. http://dx.doi.org/10.47886/9781934874257.ch42.
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<em>Abstract</em>.—Blue catfish <em>Ictalurus furcatus</em> are a commercially and recreationally important species throughout their range, in which many states have differing management strategies. Before management strategies can be implemented to achieve specific goals, understanding seasonal habitat use and movement patterns is necessary to determine the appropriate spatial scale for management. Therefore, we determined the extent and timing of blue catfish movement in the upper Mississippi River (UMR). During fall 2006 through spring 2010, 92 blue catfish (ranging from 490 to 1,025 mm total length) were captured, implanted with ultrasonic transmitters, and released in the Lock and Dam 26 area. Movement was quantified in the UMR from below Lock and Dam 19 down to the Ohio River confluence, including major tributaries, by examining the average (kilometers moved between detections/number of detections) and maximum (total number of kilometers moved across all detections) movements for each fish throughout the life of each transmitter that was detected multiple times by the stationary receiver array. Of the 82% of fish detected by stationary receivers, movement occurred from Mississippi River kilometer 459 to the Ohio River confluence, with individual blue catfish movement ranging from a maximum of 689 river kilometers to a minimum of 1.3 river kilometers. Fifteen (19%) of the fish tagged in the UMR moved into one or more of major tributaries (the Missouri, Illinois, Meramec, and Ohio rivers) while 31 (41%) of the fish stayed in the Alton area year-round and 30 (40%) blue catfish moved down into the open river to possibly overwinter. When investigating total movement by tagged blue catfish each month, the greatest movement occurred during periods of changing water temperatures and high discharge. This was further supported by the Akaike’s information criterion, with the interactive model of temperature and discharge resulting in the most support for triggering blue catfish movement. Understanding these movement patterns and seasonal habitat requirements for spawning, foraging, or refuge of riverine fish is essential for effective management of these highly mobile fish.
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Liu, J., und Q. Zhang. „Quantitative analysis of variability in modal frequencies of a kilometer-scale cable-stayed bridge during operating phase“. In Bridge Maintenance, Safety, Management and Life Extension, 2578–85. CRC Press, 2014. http://dx.doi.org/10.1201/b17063-388.
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Kemp, L. J., W. J. Otto und O. J. Waals. „Conceptual Design and Model Tests for a Mid-Water Floating Hyperloop Tunnel“. In ASME 2020 39th International Conference on Ocean, Offshore and Arctic Engineering. American Society of Mechanical Engineers, 2020. http://dx.doi.org/10.1115/omae2020-18785.
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Abstract Aviation has a significant impact on the global emission of greenhouse gasses. On the Northern Atlantic route alone there are over 2,500 crossings daily. This illustrates the high demand for connecting people. It is expected that this demand will only increase in the future, which will increase the emissions due to aviation even further. An alternative way for connecting people can be the hyperloop, which obtains comparable speeds while using a fraction of the energy. For intercontinental connections a tunnel would be necessary. In this study, a conceptual design of a mid-water floating hyperloop tunnel is made and tested on model scale at MARIN. In the present paper the results are discussed of model tests on a mid-water floating tunnel in Atlantic storm conditions at various wave directions and tunnel depths. The conceptual design of the tunnel is based on (nearly) available technology. One kilometer tunnel segments with a diameter of 11 m are connected to construct a tunnel length of > 5,000 km. Model basin tests are performed on scale 1:110, where a scale model of 140 m length is tested. The tunnel is designed as a neutral buoyant tunnel to reduce complexity and costs for the mooring system. The motions, deformations and mooring line tensions for the tunnel segments are measured by force transducers, accelerometers and an optical measurement system. Due to flexibility of the slender tunnel segments in combination with a soft mooring system, the tunnel tends to following the incoming waves for certain tunnel depths and wave directions. Only small motions and deformations are allowed for a hyperloop capsule to travel on high speed. The conceptual tests show first results on tunnel depth, structural and geometrical design of an hyperloop tunnel and mooring system.
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Lei, Jun-Qing, Xian-Qing Zhang, Shu-Lun Guo, Zu-Wei Huang und Wu-Qin Wang. „Mechanics analysis of long span railroad cable-stayed bridge under effect of vertical loads“. In IABSE Congress, Christchurch 2021: Resilient technologies for sustainable infrastructure. Zurich, Switzerland: International Association for Bridge and Structural Engineering (IABSE), 2021. http://dx.doi.org/10.2749/christchurch.2021.0554.
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<p>This paper aims to explore the challenge of the design of over one-kilometer-long span road-rail cable-stayed bridge. Because of the large live load and the weight of the structure itself, it has important theoretical significance and engineering application value to study the design parameters of the long Road-Rail cable-stayed bridge with a main span of over 1000 m. The main content of this paper is to study the Steel Road-Rail Cable-stayed Bridge with a main span of 1200 m. The finite element model is established by large-scale analysis software to calculate the response of the structure under load. Based on the calculation results, the rationality of long-span cable-stayed bridge are preliminarily researched. Wind and seismic loads are not considered.</p>
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Jana, R., P. S. Rajagopal, A. Vinod Kumar, V. D. Puranik und A. Runchal. „Limited Area Air Quality Modeling in Geographic Scale Through Flow Field Validation in Hilly Terrain“. In ASME 2013 Heat Transfer Summer Conference collocated with the ASME 2013 7th International Conference on Energy Sustainability and the ASME 2013 11th International Conference on Fuel Cell Science, Engineering and Technology. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/ht2013-17681.
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The turbulent motion of atmosphere adjoined to the earth’s surface is caused by the surface friction and buoyancy force in a short time scale which is of the order of few seconds to minutes. This interactive layer is atmospheric boundary layer with several detailed features viz., roughness layer, surface layer for small eddies, mixed layer for large eddies, which may extend vertically more than a kilometer under deep convective condition. The surface layer is primarily characterised through several scaling parameters, viz., roughness length, momentum flux and sensible heat flux as triggering force of turbulence and its maintenance through eddy formation and dissipation. Air dispersion and hence the distribution of atmospheric pollutants from various sources follow flow path and its turbulent characteristics, which is dependent on geometry of the terrain specially for complex terrain, meteorological conditions and source term inventories. In the present study, an virtual environment is designed in a computational fluid dynamics based solver for limited area/local scale air quality modelling by incorporating digital elevation model of intermediate valley zone of Sahyadri Range of Western Ghats of India as site. Finite volume method and mass flux transfer approach is followed by the solver to estimate 3D atmospheric or ground level concentration of atmospheric non-reactive pollutants for unit discharge per second from a hypothetical 100 m tall stack for 72 hours. Flow field is computed for various realistic cases for which initial and boundary conditions are incorporated from larger scale model, viz., Mesoscale Model (MM5) developed by the National Centre for Atmospheric Research, USA and also from measured local data taken from distributed micro-meteorological observatories. Computed flow field is validated with independent observation not utilised in computation giving a validation to the estimated contaminant concentration so. The uncertainty in diffusion is also studied when Lagrangian particle movement is driven fully by flow field and its turbulent phenomena in comparison to random walk model.
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Aiman, Tabony, und Llabres-Valls Enriqueta. „The Agrarian City in the age of Planetary Scale Computation: Dynamic System Model and Parametric Design Model for the introduction of Vertical Farming in High Dense Urban Environments in Singapore“. In International Conference on the 4th Game Set and Match (GSM4Q-2019). Qatar University Press, 2019. http://dx.doi.org/10.29117/gsm4q.2019.0018.
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Current conditions related to food security lead to study alternative forms of food production in cities such as vertical urban farming in high dense urban environments. This paper discusses the development of the Innovate UK award-winning project consisting of a dynamic system model that generates a large dataset of artificial environments linked to a multi-objective optimization model of urban massing for one square kilometer of development along the coastline of Singapore. The scope of the model is to reach the highest level of self-sufficiency in relation to food consumption. The model operates, as a dynamic system constituted of different subsystems including transport, water, agriculture and energy. These systems dynamically interact among each other and with their environment, which is considered the primary source of energy and the main provider of hydrological resources. A large dataset of artificial environments is created employing a Dynamic System Modelling Software; this includes different scenarios of environmental stress such as sea level rise, population growth or changes on the demand side. Such dataset of artificial environments serves as an input for the multi-objective optimization model that employs genetic algorithms to produce a large data set of urban massing including the distribution of a range of food production technologies in relation to pre-established conditions for vertical urban agriculture and compatibility with other urban programs. Connectivity, solar radiation and visual cones are the fitness criteria against which the model has been tested. This paper assesses whether artificial environments further away from the pareto front produce populations of urban design solutions that respond to extreme environmental conditions and environmental shocks.