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Micro-macro models for viscoelastic fluids: modelling, mathematics and numerics  [PDF]
C. Le Bris,T. Lelièvre
Physics , 2011,
Abstract: This paper is an introduction to the modelling of viscoelastic fluids, with an emphasis on micro-macro (or multiscale) models. Some elements of mathematical and numerical analysis are provided. These notes closely follow the lectures delivered by the second author at the Chinese Academy of Science during the Workshop "Stress Tensor Effects on Fluid Mechanics", in January 2010.
Macro to Micro Viewpoint of Climate Change - Linking Karnataka to Global Issue  [PDF]
Sunil Nautiyal
Natural Resources (NR) , 2011, DOI: 10.4236/nr.2011.21004
Abstract: A numerous studies have been done on climate change at regional, national and global levels. Several climate models have predicted the global scenarios for climate in different parts of the world. However, the significance and practical implementation of such models at local level yet to be validated. This is because those national or global models do not consider micro variables such as such as environmental resources for example ‘land availability, local climatic conditions, socioeconomic factors such as ‘labour and capital’, policy aspects such as ‘subsidies, nature conservation strategies’ and competition for labor and capital in relation of ‘national economy’. India, with a huge diversity in land, topography, climate and socioeconomic conditions, divided into 15 agro-ecological zones. Further, to help develop location specific research and development strategies at the micro level, a total of 127 sub-zones (agro-climatic sub regions) have been identified in India. Therefore, research on climate change and its impact only at the regional or national level may not be a sound approach to provide solutions for adaptation to climate change at micro level. Thus the micro-level research needs to be undertaken that might help us understand climate change impacts on the landscape i.e. biodiversity, health, natural resource management, land use and land cover development, adaptation and the development of socio-ecological systems. The concepts presented in this article should provide the basis for a discussion on decision-making issues among multidisciplinary experts with regard to climate change and sustainable development within complex environments.
Micro-macro numerical simulation of rod-like polymeric solutions

Su Jin,Ouyang Jie,Wang Xiao-Dong,

物理学报 , 2010,
Abstract: In this paper the complex rheological behaviors of rod-like polymer solutions in plane Couette flow are studied using micro-macro simulation. The micro-macro model is described by Doi theory with local inhomogeneous fluid. The finite volume method is used to solve the conservation equation on the macroscopic level and the Smoluchowski equation on the microscopic level in the numerical simulation. The numerical results predict several plane flow modes including some typical plane modes and two new complicated modes. Furthermore, simulation results show that the rheological phase diagrams for solutions of rigid rod molecules are mainly dependent on the Deborah number, the concentration of solutions and molecular scale, and the varying Deborah number have great influence on some micro-properties of tumbling period and orientation angle of flow-aligning.
An institutional perspective on the micro-macro link.  [cached]
de Nooy, Wouter
REDES : Revista Hispana para el Análisis de Redes Sociales , 2002,
Abstract: The micro-macro link may be regarded as a dynamic process in which actors interpret local patterns of relations as indicators or elements of an overarching structure, communicate their interpretations, and adjust their relations to the overall structure as they perceive it. In this paper, it is proposed that actors perceive local substructures in a network of evaluations, such as dyads, triads, or short semicycles, and infer clustering and ranking in ways that are compatible with balance-theoretic models. They interpret and communicate the information as simplified and idealized classifications resembling blockmodels, to which they adjust their relations afterwards. In this way, the ego-centered and socio-centered perspectives are dynamically related.This approach is applied to evaluations among authors and critics in the literary institution. At the micro level, literary authors and critics adjust their evaluations to previous evaluations. At the global level, the institution of literature is stratified into clusters, e.g., literary movements and styles. The members of this institution reflect on its structure: classifications according to movement and style are communicated and discussed in literary criticism.
A Stochastic Rheological Model for the Calculation of Polymeric fluids  [cached]
Deepthika Senaratne
International Journal of Advancements in Technology , 2010,
Abstract: A stochastic rheological model for the calculation of polymer stress in polymeric fluids is developed and evaluated. The model is microscopic-based and combines aspects of reptation, modified network and continuum models. A concentrated Polyisobutylene (PIB) solution is simulated for material functions in various rheometric flows. Comparisons made with available experimental data shows that the model predicts well the qualitative material behavior of the fluid in the rheometric flows considered. In most cases, the predictions agree quantitatively with the available experimental data.
Micro and Macro Causes of Violence  [cached]
Randall Collins
International Journal of Conflict and Violence , 2009,
Abstract: The dominant emotion in violence-threatening situations is confrontational tension/fear (ct/f), which causes most violence to abort, or to be carried out inaccurately and incompetently. For violence to be successful, there must be a pathway around the barrier of ct/f. These pathways include: attacking the weak; audience-oriented staged and controlled fair fights; confrontation-avoiding remote violence; confrontation-avoiding by deception; confrontation-avoiding by absorption in technique. Successfully violent persons, on both sides of the law, are those who have developed these skilled interactional techniques. Since successful violence involves dominating the emotional attention space, only a small proportion of persons can belong to the elite which does most of each type of violence. Macro-violence, including victory and defeat in war, and in struggles of paramilitaries and social movements, is shaped by both material resources and social/emotional resources for maintaining violent organizations and forcing their opponents into organizational breakdown. Social and emotional destruction generally precedes physical destruction.
Existence of weak solutions for unsteady motions of micro-polar electrorheological fluids  [PDF]
E. Baeumle,M. Ruzicka
Mathematics , 2015,
Abstract: In this paper we study the existence of weak solutions to an unsteady system describing the motion of micro-polar electrorheological fluids. The constitutive relations for the stress tensors belong to the class of generalized Newtonian fluids. Using the Lipschitz truncation and the solenoidal Lipschitz truncation we establish the existence of global solutions for shear exponents $p>6/5$ in three-dimensional domains.
Micro- and nano-structured conducting polymeric materials
Gewu Lu,Feng’en Chen,Xufeng Wu,Liangti Qu,Jiaxin Zhang,Gaoquan Shi
Chinese Science Bulletin , 2005, DOI: 10.1360/982005-670
Abstract: Conducting polymeric materials with micro-/ nano-structures have potential applications in fabrication of various optical, electronic, sensing and electrochemical devices. This is mainly because these materials not only possess the characteristics of conducting polymers, but also have special functions based on their micro- or nano-structures. In this review, we summarize the recent work on “soft” and “hard” template-guided syntheses of micro-/nano-structured conducting polymers and open up the prospects of the main trends in this field.
Global existence of weak solutions to the FENE dumbbell model of polymeric flows  [PDF]
Nader Masmoudi
Mathematics , 2010,
Abstract: Systems coupling fluids and polymers are of great interest in many branches of sciences. One of the models to describe them is the FENE (Finite Extensible Nonlinear Elastic) dumbbell model. We prove global existence of weak solutions to the FENE dumbbell model of polymeric flows for a very general class of potentials. The main problem is the passage to the limit in a nonlinear term that has no obvious compactness properties. The proof uses many weak convergence techniques. In particular it is based on the control of the propagation of strong convergence of some well chosen quantity by studying a transport equation for its defect measure.
Exotic fluids and crystals of soft polymeric colloids  [PDF]
Christos N Likos,Norman Hoffmann,Hartmut Lowen,Ard A Louis
Physics , 2002, DOI: 10.1088/0953-8984/14/33/309
Abstract: We discuss recent developments and present new findings in the colloidal description of soft polymeric macromolecular aggregates. For various macromolecular architectures, such as linear chains, star polymers, dendrimers and polyelectrolyte stars, the effective interactions between suitably chosen coordinates are shown to be ultrasoft, i.e., they either remain finite or diverge very slowly at zero separation. As a consequence, the fluid phases have unusual characteristics, including anomalous pair correlations and mean-field like thermodynamic behaviour. The solid phases can exhibit exotic, strongly anisotropic as well as open crystal structures. For example, the diamond and the A15-phase are shown to be stable at sufficiently high concentrations. Reentrant melting and clustering transitions are additional features displayed by such systems, resulting in phase diagrams with a very rich topology. We emphasise that many of these effects are fundamentally different from the usual archetypal hard sphere paradigm. Instead, we propose that these fluids fall into the class of mean-field fluids.
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