The study of the dynamic effects caused by human activities over structural systems has gained a significant relevance during the last few years. On the other hand, some recently constructed pedestrian footbridges hav...
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This paper describes the numerical modelling of the structural behaviour of the church of San Francesco in Lucca, Italy. The constitutive equation for the various types of masonry employed in historic buildings views ...
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Based on the numerical example, the article presents the possibilities of mathematicalmodelling for testing the transport systems. On the basis of the conducted analysis of the transport system model, it was shown th...
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Assessment of an oil-spill behaviour in the maritime environment is absolutely necessary, as a great amount of petroleum is transported by cargo ships and pipelines through this environment. Moreover, the increase in ...
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New experimental evidence shows that hollow fibre membrane bioreactor (HFMB) may be applied to grow bulky bone tissues which may then be implanted into patients to repair skeletal defects. To design effective bone tis...
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New experimental evidence shows that hollow fibre membrane bioreactor (HFMB) may be applied to grow bulky bone tissues which may then be implanted into patients to repair skeletal defects. To design effective bone tissue engineering protocols, it is necessary to determine the quantitative relationships between the cell environment and tissue behaviour in HFMBs and their relationship with nutrient supply. It is also necessary to determine under what conditions nutritional limitations may occur and, hence, may cause cell death. These require that the appropriate bioreactor conditions for generating neotissues, and the nutrient transfer behaviour and chemical reaction during cell growth and extracellular matrix formation are studied thoroughly. In this paper, we aim to use an existing mathematical framework to analyse the influence of various relevant parameters on nutrient supply for bone tissue growth in HFMB. We adopt the well-known Krogh cylinder approximation of the HFMB. The model parameters ( e. g., cell metabolic rates) and operating conditions for the mathematical model have been obtained from, or correspond to, in-house experiments with the exception of a few variables which have been taken from the literature. The framework is then used to study oxygen and glucose transport behaviour in the HFMB. Influence of a number of important process parameters, e. g., reaction kinetics, cell density, inlet concentration of nutrients, etc, on the nutrient distributions have been systematically analysed. The work presented in this paper provides insights on unfavourable system designs and specifications which may be avoided to prevent mass transfer limitations for growing bone tissues in HFMB.
The article deals with the creation of a human tibia 3D model by means of "Autodesk Revit-2016" PC based on tomogram data. The model was imported into "Lira-SAPR2013 R4" software system. To assess ...
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The article deals with the creation of a human tibia 3D model by means of "Autodesk Revit-2016" PC based on tomogram data. The model was imported into "Lira-SAPR2013 R4" software system. To assess the possibility of education and the nature of bone fracture (and their visualization), the Finite Element Analysis (FEA) method was used. The geometric parameters of the BBK model corresponded to the physical parameters of the individual. The compact plate different thickness is modeled by rigidity properties of the finite elements in accordance with the parameters on the roentgenogram. The BBK model included parameters of the outer compact plate and the spongy substance having a more developed structure of the epiphysic region. In the "Lira-SAPR2013 R4" software system, mathematical modeling of the traumatic effect was carried out and the analysis of the stress-strain state of the finite element model of the tibia was made to assess fracture conditions.
The paper presents a recently developed constitutive model for unsaturated soils, based on the theory of hypoplasticity and the effective stress principle. The mathematical formulation of the model is outlined and the...
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In order to display huge scenes with virtual human inhabitants evolving inside a virtual city, we propose a methodology to create and manage different Level of Detail for a well-segmented scene without "re-meshin...
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ISBN:
(纸本)0769505775
In order to display huge scenes with virtual human inhabitants evolving inside a virtual city, we propose a methodology to create and manage different Level of Detail for a well-segmented scene without "re-meshing" the scene during simulation. A database dedicated to urban life simulation providing data for planning human actions and behaviour is completed such a way to furnish information about the most adapted displayed representations.
The mathematical approach is the most commonly used approach in reservoir simulation. The classical mathematical approach considers numerous impractical assumptions leading toward the development of unrealistic reserv...
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The mathematical approach is the most commonly used approach in reservoir simulation. The classical mathematical approach considers numerous impractical assumptions leading toward the development of unrealistic reservoir simulator. In contrast, recently developed engineering approach is much promising as it has numerous advantages, such as – scope of bypassing the formulation of partial differential equations and discretization of partial differential equations, the ability to avoid rigorous and complex mathematics, and capability of realistic representation of reservoir behaviour through eliminating spurious assumptions. The present study outlines the route map for developing a reservoir simulator using an engineering approach. Major challenges encountered in reservoir simulation and the fundamentals of various available modelling approaches are addressed in this paper. The outlook for both classical mathematical approach and engineering approach are reviewed along with their strengths and weaknesses. Fluid flow equations are derived based on the proposed engineering approach. To do that, a set of non-linear algebraic flow equations in the time integral form is developed using the mass balance equation, an equation of state, and a constitutive equation without going through the formulation of partial differential equations and discretization step. The time integral is then approximated to obtain the non-linear algebraic flow equations for all the gridblocks of the reservoir. The significance of the engineering approach for describing the accurate fluid flow through porous media is compared to the to conventional mathematical approach. The engineering approach provides the same fluid flow equations as the classical mathematical approach for both the radial cylindrical and cartesian coordinate system but, without going through the formulation of partial differential equations and discretization step. Much simpler ordinary differential equation solvers, e.g., Runge-Ku
This paper describes an application of conceptual graphs in knowledge engineering. We are developing an assistance system for the acquisition and the validation of stereotyped behaviour models in human organizations. ...
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ISBN:
(纸本)3540633081
This paper describes an application of conceptual graphs in knowledge engineering. We are developing an assistance system for the acquisition and the validation of stereotyped behaviour models in human organizations. The system is built on a representation language requiring to be at expert level, to have a clear semantics and to be interpretable. The proposed language is an extension of conceptual graphs dedicated to the representation of behaviours. Tools exploiting this language are provided to assist the construction of behaviour models and their simulation on concrete cases.
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