Search results for "model [particle]"
showing 10 items of 1261 documents
Dynamical heterogeneities in glass-forming materials
1996
ABSTRACTCooperative dynamics around the glass transition leads to complex motional behavior of the individual molecules, resulting in non-exponential relaxation. The nature of this non-exponentiality is clarified theoretically as well as experimentally. The non-exponentiality may be due to heterogeneous relaxation (superposition of exponential processes with different rate constants) or homogeneous relaxation (identical intrinsically non-exponential processes). A precise definition of both limits is given. It is shown that the type of relaxation, i.e. to which degree heterogeneous and homogeneous contributions are present, reflects geometrical properties of the dynamics. The heterogeneous c…
Solid State NMR Structure Analysis of the Antimicrobial Peptide Gramicidin S in Lipid Membranes: Concentration-Dependent Re-alignment and Self-Assemb…
2008
Antimicrobial peptides can kill bacteria by permeabilizing their cell membrane, as these amphiphilicmolecules interact favourably with lipid bilayers. This mechanism of action is attributed eitherto the formation of a peptide “carpet” on the membrane surface, or to a transmembranepore. However, the structure of such a pore has not yet been resolved under relevant conditions.Gramicidin S is a symmetrical cyclic β-sheet decapeptide, which has been previouslyshown by solid state NMR to lie flat on the membrane surface at low peptide:lipid ratios (≤ 1:80).Using highly sensitive 19F-NMR, supported by 15N-labelling,we found that gramicidin S can flip into an upright transmembrane alignment at hig…
ChemInform Abstract: Cobalt Clusters with Cubane-Type Topologies Based on Trivacant Polyoxometalate Ligands.
2016
Four novel cobalt-substituted polyoxometalates having cobalt cores exhibiting cubane or dicubane topologies have been synthesized and characterized by IR, elemental analysis, electrochemistry, UV–vis spectroscopy, X-ray single-crystal analysis, and magnetic studies. The tetracobalt(II)-substituted polyoxometalate [Co4(OH)3(H2O)6(PW9O34)]4– (1) consists of a trilacunary [B-α-PW9O34]9– unit which accommodates a cubane-like {CoII4O4} core. In the heptacobalt(II,III)-containing polyoxometalates [Co7(OH)6(H2O)6(PW9O34)2]9– (2), [Co7(OH)6(H2O)4(PW9O34)2]n9n– (3), and [Co7(OH)6(H2O)6(P2W15O56)2]15– (4), dicubane-like {CoII6CoIIIO8} cores are encapsulated between two heptadentate [B-α-PW9O34]9– (in…
A new interpretation for the structure of the VN bands of ethylene
1971
Abstract Potential surfaces for CC stretch and CH2 twisting of ethylene obtained by the combined SCF CI method lead to the prediction that non-vertical transitions are responsible for the absorption maximum in the VN bands and that the broad diffuse nature of the spectrum in this region could well be caused by the proximity of two states of the same symmetry of the twisted molecule.
Hunting for new physics signals in the LHC era
2021
Actualment, el ME de física de partícules és capaç d’explicar satisfactòriament tres de les quatre interaccions fonamentals de la matèria: fortes, febles i electromagnètiques. Tot i això, hi han molts aspectes que aquesta fantàstica teoria no és capaç d’explicar i, sens dubte, ha d’haver alguna cosa més enllà d’aquesta teoria. En aquesta tesi es pretén descobrir si hi ha algun indici a les dades actuals dels acceleradors que suggerisca l’existència de nova física (NF). Pretenem, per tant, determinar fins a quin punt alguns dels models de NF que han sigut proposats a la literatura poden ser plausibles tenint en compte les dades actuals. D’aquesta forma, serem capaços de trobar restriccions s…
Modèle des voies réflexes et cérébelleuses, permettant le calcul de fonctions inverses et la commande d'un segment mécanique mobile
2004
14/07/2004; La commande et le contrôle des mouvements des membres par les voies cérébelleuses et réflexes sont modélisées au moyen d'un circuit dont la structure est déduite de contraintes fonctionnelles. 1/ La première contrainte est que les mouvements rapides des membres doivent être précis, quoiqu'ils ne puissent pas être commandés en boucle fermée au moyen de signaux sensoriels. Les voies qui préparent les ordres moteurs doivent donc contenir des fonctions inverses approximées des fonctions biomécaniques du membre et des muscles. Or une telle fonction peut être calculée au moyen de boucles de rétroaction parallèles, dont la structure est comparable à l'anatomie des voies cérébelleuses. …
Bionika vidusskolas fizikas mācību satura apguvē
2013
ANOTĀCIJA Promocijas darba „ Bionika vidusskolas fizikas mācību satura apguvē” mērķis - izpētīt vidusskolas fizikas mācību saturu, bionikas ieviešanas iespējamību fizikas apguves procesā, izstrādāt skolēnu zināšanas par dabu integrējošu didaktisko modeli, kas sekmē dabaszinību un tehnoloģiju kompetences attīstību un veicina intereses veidošanos par dabaszinātnēm. Pētījumā veikta literatūras un izglītības dokumentācijas analīze par fizikas mācību procesa īstenošanas pedagoģiski psiholoģiskajiem aspektiem, par mācību satura attīstību konstruktīvā, uz kontekstiem balstītā pedagoģiskajā procesā, izstrādāts skolēnu zināšanas par dabu integrējošs didaktiskais modelis, integrējot bioniku vidusskol…
Predictive control of convex polyhedron LPV systems with Markov jumping parameters
2012
The problem of receding horizon predictive control of stochastic linear parameter varying systems is discussed. First, constant coefficient matrices are obtained at each vertex in the interior of linear parameter varying system, and then, by considering semi-definite programming constraints, weight coefficients between each vertex are calculated, and the equal coefficients matrices for the time variable system are obtained. Second, in the given receding horizon, for each mode sequence of the stochastic convex polyhedron linear parameter varying systems, the optimal control input sequences are designed in order to make the states into a terminal invariant set. Outside of the receding horizon…
From Agile Software Development to Mercury Business
2014
The rapid downfall of the Nokia software ecosystem has radically altered the landscape of software industry in Finland in recent years. There has been a shift from largely corporate driven way of working, which is often dominant in large companies, to more agile practices, and in general software organizations are seeking new, leaner ways of composing, delivering, and using software also inside already established companies. To accelerate this transformation in large scale, a collaborative research program has been created, called Need for Speed (N4S). In this paper, we give an insight to the joint goals and concrete actions of the program and discuss the motivations of individual companies…
An analysis of model predictive control with integral action applied to digital displacement cylinders
2020
This article aims to analyze Model Predictive Control (MPC) for the control of multi-chamber cylinders. MPC with and without integral action has been introduced. Three different algorithms have been used to solve the optimization problem in the MPC. The different algorithms have been compared with an industrial solver. The influence of changing mass, choosing a different middle line pressure, system delays, signal noise, velocity estimation, and changing pressure levels has been investigated. It is concluded that for the small prediction horizon used in the paper a simple algorithm such as A can produce results as good as the previously used Differential Evolution algorithm in less than hal…