Systems engineering, multiscale

The main objective of this work is to discuss recent developments in molecular simulation, multiscale simulation and multiscale systems engineering, and how these developments enable the targeted design of processes and products at the molecular scale. The control of events at the molecular scale is critical to product quality in many new applications in medicine, computers and manufacturing. 

The anticipated benefits of multiscale simulation to society are substantial. For example, the NSF Blue Ribbon Panel report on Simulation-based Engineering Science (http //www.nsf.gov/pubs/reports/sbes final report.pdf) describes benefits of accurate predictions for multiscale systems which include ... 

On the other hand, well engineered manufacturing operations depend on the availability of manipulated variables for real-time feedback control. These variables usually operate at macroscopic length scales (e.g. the power to heat lamps above a wafer, the fractional opening of valves on flows into and out of a chemical reactor, the applied potential across electrodes in an electrochemical process). The combination of a need for product quality at the molecular scale with the economic necessity that feedback control systems utilize macroscopic manipulated variables motivates the creation of methods for the simulation, design and control of multiscale systems. 

Future trends in electrochemical engineering will be influenced by the need to develop molecular-based discoveries into new and improved products and processes. What is needed is to develop a multiscale systems approach that builds upon the traditional base of continuum-scale mathematical models. 

More recently, techniques have been developed for utilizing multiscale simulation models to perform systems engineering tasks, such as parameter estimation, optimization and control (e.g. see reviews by [9, 10] and [11], and references cited therein). This incorporation of models that couple molecular through macroscopic length scales within systems engineering tools enables a systematic approach to the simultaneous optimization of all of the length scales of the process. 

The multiscale system also appears to be capable of providing more enhanced biological functionality, particularly for vascularization, which is favored by the interaction of ECs with the nanofibrous network.s that allow suitable cell architecture and orientation for microtubule formation. Thus, the synergistic effect of micro- and nanoscales could successfully regenerate natural tissues in vivo in the near future. Future work should focus on optimizing this process to better recapitulate key features of the native ECM, including its mechanical and biochemical properties, which would enhance the functionality of these 3D multiscale scaffolds in order to fabricate functional tissue engineered constructs. 

Fermeglia, M. Pricl, S. Multiscale molecular modeling in nanostructured material design and process system engineering. Comput. Chem. Eng. 33 (2009), pp. 1701-1710. 

Two important challenges exist for multiscale systems. The first is multiple time scales, a problem that is familiar in chemical engineering where it is called stiffness, and we have good solutions to it. In the stochastic world there doesn t seem to be much knowledge of this phenomenon, but I believe that we recently have found a solution to this problem. The second challenge—one that is even more difficult—arises when an exceedingly large number of molecules must be accounted for in stochastic simulation. I think the solution will be multiscale simulation. We will need to treat some reactions at a deterministic scale, maybe even with differential equations, and treat other reactions by a discrete stochastic method. This is not an easy task in a simulation. 

These factors can also be organized as a multiscale optimization problem by their operations, which is seen in table 11.5. The chemistry of manufacturing is mostly concerned with the nanometer to micrometer scales of molecules and colloids, and process engineering is mostly concerned with the millimeter to meter scales of components and equipment. The systems of plants and markets operate in the kilometer scale, and the global environment operates in the thousand kilometer scale. 

Dionisio Vlachos, A Review of Multiscale Analysis Examples from System Biology, Materials Engineering, and Other Fluids-Surface Interacting Systems... 

Bennethum, L.S. and Cushman, J.H. (1996) Multiscale, hybrid mixture theory for swelling systems - II Constitutive theory, International Journal of Engineering Science 34(2), 147-169... 

Ukidwe, N. W. and Bakshi, B.R., A multiscale Bayesian framework for designing efficient and sustainable industrial systems, AlChE Sustainability Engineering Conference Proceedings, Austin, TX, November, pp. 179-187, 2004. 

A REVIEW OF MULTISCALE ANALYSIS EXAMPLES FROM SYSTEMS BIOLOGY, MATERIALS ENGINEERING, AND OTHER FLUID-SURFACE INTERACTING SYSTEMS... 

Science in 2004 that have been dedicated to Complex Systems and Multi-scale Methodology, the forth issue of the 29th volume in Computers in Chemical Engineering on Multiscale Simulation published in 2005, the Springer-Verlag IMA edited book on Dispersive Transport Equations and Multiscale Models resulting from a related workshop, numerous workshops, and a topical conference on Multiscale Analysis in the 2005 AIChE meeting, just to mention a few. 

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