Search results for "Simulation."
showing 10 items of 4779 documents
Hub-Centered Gene Network Reconstruction Using Automatic Relevance Determination
2012
Network inference deals with the reconstruction of biological networks from experimental data. A variety of different reverse engineering techniques are available; they differ in the underlying assumptions and mathematical models used. One common problem for all approaches stems from the complexity of the task, due to the combinatorial explosion of different network topologies for increasing network size. To handle this problem, constraints are frequently used, for example on the node degree, number of edges, or constraints on regulation functions between network components. We propose to exploit topological considerations in the inference of gene regulatory networks. Such systems are often…
A perturbation approach for the response of dynamically modified structural systems
1998
The problem of the structural analysis under changes of dynamical parameters is of particular interest. This is due to the fact that often the real structures are different from the predicted ones. In this paper, an unconditionally stable step-by-step procedure, able to evaluate the deterministic response of linear structures with modifications, is presented. The proposed procedure requires the evaluation of the transition matrix, which is the fundamental operator of the step-by-step solution, by means of a perturbation approach. This technique overcomes the difficulties connected with the evaluation of the eigenproperties of the modified structures usually required to obtain the transition…
Teaching process control in food engineering: dynamic simulation of a fermentation control process
2017
Abstract Students usually have difficulties to understand abstract concepts of process control. Implementing in teaching process the inquiry-based learning helps students to follow methods and practices similar to those of professional scientists in order to construct knowledge. The paper describes the steps reached in simulation-based learning: from experimental data obtained by the students in their practical method (study and measurement of variables to some fermentation processes) to the simulated the behaviour of the process under a feedback control system. By providing opportunities for students to check their understanding and reflect on their learning process performance is enhanced…
Simulator for a Natural Gas Storage Realised in Depleted Deposit
2014
The present paper presents the implementation of a numerical model for a natural storage transformed into a deposit which takes into consideration the geometry of the storage, the properties of the rocks and in which the movements of the gases can be described. The model is two-dimensional nonstationary and allows the dynamic simulation of the processes of injection and extraction. The location of the wells and their flows can be thus studied and optimized to maximize the amount of the stored gases. The presented model allows the quick finding of solutions for a whole cycle of storage in a short time so that it could be used successfully in the operation process.
A Dynamic Simulation of a Human Gait Using the Hybrid Muscle Model and a QCT-Based Flexible Tibia
2009
The flexible multibody simulation [9] approach can be used in a wide variety of engineering applications. In a previous study of authors [1], flexible multibody simulation approach was used to estimate strains during walking at tibial midshaft. In the previous study, simple muscle models were used in conjunction with a flexible tibia model based on magnetic resonance images (MRI). This study is an extension of the previous developments [1], [2] demonstrating the potential of model improvement by introducing hybrid muscle models, along with the flexible tibia based model on computed tomography (CT). The computed tomography technique allows for the accounting of inhomogeneous density and elas…
Embedded Model Control and dynamic simulation
2006
Embedded model control (EMC) is and end-to-end control technology addressed to industrial engineers and centered on the embedded model, a stylized discrete-time state equation of the whole plant, including environment, communication and computing resources. The embedded model, which is the core of the control unit, is derived and validated from a fine model of the plant which is implemented as a simulator code. The latter acts as a faithful and friendly test-bench where assessing control units before they are loaded into target processor. The paper illustrates the requirements and architecture of the EMC simulator under continuous improvement. A case study closes the paper.
A distributed dynamic load balancer and its implementation on multi-transputer systems for molecular dynamics simulation
1990
Abstract A new and efficient approach is described to the dynamic load-balancing problem which is central in concurrent computing. A transputer-based implementation is tested on a molecular dynamics simulation of spinodal phase separation.
Dynamic Simulation of Worm Gears Using CAD Applications
2021
The new processes by plastic deformation of the gears eliminate some of the shortcomings of the old methods of their manufacture, at the same time reducing the production costs and the time of realization of the mass production. To carry out this research, the AutoDesk INVENTOR PROFESSIONAL application was chosen. A worm gear was designed, after which the calculations for the worm and worm wheel were performed. Of particular importance for gear, mechanisms are the research of dynamic loads. The use of modern calculation methods, which have wide possibilities for rapid optimization of prototypes, ensures the minimization or sometimes even exclusion of the execution of experimental samples. T…
Comparative Study of the Mechanical Unfolding Pathways of α- and β-Peptides
2015
Using molecular simulations, we analyze the unfolding pathways of various peptides. We compare the mechanical unfolding of a β-alanine's octamer (β-HAla8) and an α-alanine's decamer (α-Ala10). Using force-probe molecular-dynamics simulations, to induce unfolding, we show that the 3(14)-helix formed by β-HAla8 is mechanically more stable than the α-helix formed by α-Ala10, although both structures are stabilized by six hydrogen bonds. Additionally, computations of the potential of mean force validate this result and show that also the thermal stability of the 3(14)-helix is higher. It is demonstrated that β-HAla8 unfolds in a two-step fashion with a stable intermediate. This is contrasted wi…
Climate change impact on SWAT simulated streamflow in western Kenya
2009
12 pages (3/4 p.); International audience; Weather and climate extremes such as droughts and floods have far reaching impacts in Kenya. They have had implications in a variety of sectors including agriculture, water resources, health, energy, and disaster management among others. Lake Victoria and its catchment support millions of people and any impact on its ability to support the livelihoods of the communities in this region is of major concern. Thus, the main objective of this study was to assess the potential future climatic changes on the Nzoia catchment in the Lake Victoria basin, and how they might affect streamflow. The Soil and Water Assessment Tool was used to investigate the impa…