{ "types" : { "Bookmark" : { "pluralLabel" : "Bookmarks" }, "Publication" : { "pluralLabel" : "Publications" }, "GoldStandardPublication" : { "pluralLabel" : "GoldStandardPublications" }, "GoldStandardBookmark" : { "pluralLabel" : "GoldStandardBookmarks" }, "Tag" : { "pluralLabel" : "Tags" }, "User" : { "pluralLabel" : "Users" }, "Group" : { "pluralLabel" : "Groups" }, "Sphere" : { "pluralLabel" : "Spheres" } }, "properties" : { "count" : { "valueType" : "number" }, "date" : { "valueType" : "date" }, "changeDate" : { "valueType" : "date" }, "url" : { "valueType" : "url" }, "id" : { "valueType" : "url" }, "tags" : { "valueType" : "item" }, "user" : { "valueType" : "item" } }, "items" : [ { "type" : "Publication", "id" : "https://puma.ub.uni-stuttgart.de/bibtex/2e9294d19b2f705461fe8340bf970a6fb/inspo5", "tags" : [ "Endomysial","Extracellular","Fiber","Lateral","Sarcomere","bundle","connections","force","heterogeneity","length","matrix","mechanics","transmission" ], "intraHash" : "e9294d19b2f705461fe8340bf970a6fb", "interHash" : "7c13ec95eb31404c7683564d78305f64", "label" : "The impact of endomysium integrity on skeletal muscle fiber bundle mechanics", "user" : "inspo5", "description" : "", "date" : "2025-11-05 15:18:13", "changeDate" : "2025-11-05 15:18:13", "count" : 2, "pub-type": "article", "journal": "Journal of Biomechanics","publisher":"Elsevier BV", "year": "2025", "url": "http://dx.doi.org/10.1016/j.jbiomech.2025.112957", "author": [ "Paolo Carlo Danesini","André Tomalka","Tobias Siebert","Filiz Ates" ], "authors": [ {"first" : "Paolo Carlo", "last" : "Danesini"}, {"first" : "André", "last" : "Tomalka"}, {"first" : "Tobias", "last" : "Siebert"}, {"first" : "Filiz", "last" : "Ates"} ], "editor": [ "Tobias Siebert" ], "editors": [ {"first" : "Tobias", "last" : "Siebert"} ], "volume": "192","pages": "112957","abstract": "The endomysium, the innermost layer of the extracellular matrix (ECM), was shown to play an important role in both passive and active force transmission. However, its mechanical contribution within muscle fiber bundles remains incompletely understood. We hypothesized that dissecting one of the endomysial connections within a fiber bundle would alter force production and lead to changes in sarcomere lengths and their heterogeneity. Muscle fiber bundles (n = 12) were extracted from the extensor digitorum longus muscles of rats and chemically skinned. Their passive and active stress-length relationships were measured under two conditions: (i) with intact endomysium and (ii) after blunt dissection of endomysial connections between two adjacent peripheral fibers. Disruption of endomysial continuity significantly reduced passive stress by 26.5 % (p < 0.01) and active stress by 21.9 % (p < 0.001) on average across all lengths tested. It also shifted the optimal fiber length (Lopt) to longer values by 6.2 % (p < 0.01). Despite these mechanical changes, average sarcomere lengths (along fibers) and their heterogeneity remained unchanged. Length heterogeneity was only observed at a longer fiber length (1.3 Lopt) in the passive state before dissection. These findings demonstrate that endomysial connections are integral to the mechanical behavior of muscle fiber bundles, influencing both passive and active stress. The absence of sarcomere length changes along fibers suggests that other microstructural mechanisms, such as altered lattice spacing or impaired lateral force transmission, may underlie the observed changes. These results highlight the importance of ECM integrity in muscle mechanics and have implications for orthopedic interventions and neuromuscular disorder management.", "issn" : "0021-9290", "doi" : "10.1016/j.jbiomech.2025.112957", "bibtexKey": "Danesini_2025" } , { "type" : "Publication", "id" : "https://puma.ub.uni-stuttgart.de/bibtex/283fba02b010557af3f547c378cdb6de6/inspo5", "tags" : [ "Connective","Endomysium","Extracellular","Intramuscular","Muscle","fiber","force","integrity","matrix","tissue","transmission" ], "intraHash" : "83fba02b010557af3f547c378cdb6de6", "interHash" : "2d12b002242e8974ec406082ad65e8b3", "label" : "Endomysium determines active and passive force production in muscle fibers", "user" : "inspo5", "description" : "", "date" : "2024-05-08 11:25:57", "changeDate" : "2024-08-07 11:33:21", "count" : 8, "pub-type": "article", "journal": "Journal of Biomechanics","publisher":"Elsevier BV", "year": "2024", "url": "http://dx.doi.org/10.1016/j.jbiomech.2024.112134", "author": [ "Paolo Carlo Danesini","Maximilian Heim","André Tomalka","Tobias Siebert","Filiz Ates" ], "authors": [ {"first" : "Paolo", "last" : "Carlo Danesini"}, {"first" : "Maximilian", "last" : "Heim"}, {"first" : "André", "last" : "Tomalka"}, {"first" : "Tobias", "last" : "Siebert"}, {"first" : "Filiz", "last" : "Ates"} ], "editor": [ "Tobias Siebert" ], "editors": [ {"first" : "Tobias", "last" : "Siebert"} ], "volume": "168","pages": "112134","abstract": "Connective tissues can be recognized as an important structural support element in muscles. Recent studies have also highlighted its importance in active force generation and transmission between muscles, particularly through the epimysium. In the present study, we aimed to investigate the impact of the endomysium, the connective tissue surrounding muscle fibers, on both passive and active force production. Pairs of skeletal muscle fibers were extracted from the extensor digitorum longus muscles of rats and, after chemical skinning, their passive and active force\u2013length relationships were measured under two conditions: (i) with the endomysium between muscle fibers intact, and (ii) after its dissection. We found that the dissection of the endomysium caused force to significantly decrease in both active (by 22.2 % when normalized to the maximum isometric force; p < 0.001) and passive conditions (by 25.9 % when normalized to the maximum isometric force; p = 0.034). These findings indicate that the absence of endomysium compromises muscle fiber\u2019s not only passive but also active force production. This effect may be attributed to increased heterogeneity in sarcomere lengths, enhanced lattice spacing between myofilaments, or a diminished role of trans-sarcolemmal proteins due to dissecting the endomysium. Future investigations into the underlying mechanisms and their implications for various extracellular matrix-related diseases are warranted.", "language" : "English", "issn" : "0021-9290", "doi" : "10.1016/j.jbiomech.2024.112134", "bibtexKey": "Carlo_Danesini_2024" } , { "type" : "Publication", "id" : "https://puma.ub.uni-stuttgart.de/bibtex/2fa8b4ced7ec272f4bb10e7a3612067d2/roberta.toscano", "tags" : [ "abstract,aluminium","amcs","and","and,particle","applies","comparatively,properties","compared","composites,amc,amcs,applications,great","distribution,particle-reinforced","for","forming,this","improved","matrix","mechanical","monolithic,semi-solid","particularly","potential","provide,offer","revealing","therefore","to","to,tribological","various,high,materials" ], "intraHash" : "fa8b4ced7ec272f4bb10e7a3612067d2", "interHash" : "924bffde25835c99a3551127ee91a795", "label" : "Influence of Reinforcement Particle Parameters on the Homogeneity of Particle Distribution in Semi-Solid Formed Aluminium Matrix Composites", "user" : "roberta.toscano", "description" : "", "date" : "2023-09-04 11:41:55", "changeDate" : "2023-09-13 14:11:46", "count" : 3, "pub-type": "article", "journal": "Solid State Phenomena", "year": "2023", "url": "", "author": [ "Marco Speth","Kim Rouven Riedmüller","Mathias Liewald" ], "authors": [ {"first" : "Marco", "last" : "Speth"}, {"first" : "Kim Rouven", "last" : "Riedmüller"}, {"first" : "Mathias", "last" : "Liewald"} ], "volume": "347","pages": "39--45", "bibtexKey": "Speth2023" } , { "type" : "Publication", "id" : "https://puma.ub.uni-stuttgart.de/bibtex/2e2a25c2f1d2a11f018fb3778f8dedcde/roberta.toscano", "tags" : [ "abstract,aluminium-matrix","alloy,particles,powder","composites,amc,application","composites,mmc,of","discontinuous","fibres","functional","improve","in","like","matrix","of,mechanical,metal","or","or,thermal","order,compressibility,e,g,if","pressing,properties,reinforcements","produced","requirements","specific,are","specific,using","the","tribological,to" ], "intraHash" : "e2a25c2f1d2a11f018fb3778f8dedcde", "interHash" : "b3f986dd8d5a4ff8d7f9b686f70bda0b", "label" : "Consolidation behaviour of particle reinforced aluminium-matrix powders with up to 50 vol.\\% SiCp", "user" : "roberta.toscano", "description" : "", "date" : "2023-09-04 11:41:55", "changeDate" : "2023-09-13 14:11:46", "count" : 2, "pub-type": "inproceedings", "booktitle": "Materials Research Proceedings", "year": "2023", "url": "https://www.mrforum.com/product/9781644902479-182", "author": [ "Marco Speth","Kim Rouven Riedmüller","Mathias Liewald" ], "authors": [ {"first" : "Marco", "last" : "Speth"}, {"first" : "Kim Rouven", "last" : "Riedmüller"}, {"first" : "Mathias", "last" : "Liewald"} ], "volume": "28","pages": "1689--1696", "isbn" : "9781644902479", "doi" : "10.21741/9781644902479-182", "bibtexKey": "Speth2023b" } , { "type" : "Publication", "id" : "https://puma.ub.uni-stuttgart.de/bibtex/2343f78516758162f4bb3590257e5df1a/roberta.toscano", "tags" : [ "abstract,aeronautic","achieve","and","as","as,four-way","automotive,lightweight,order","component,s","components","composites,amc,are","coupling,in,in","electrical","engineering,aluminium","for,cfd-dem,disperse","highly","homogeneous","manufacturing","matrix","of,today,yet","particle,distributions","particle,possible","stressed","these","to","used","volumes,the","widely","within" ], "intraHash" : "343f78516758162f4bb3590257e5df1a", "interHash" : "54df77ddad0c26b94f53b6ca4ca592be", "label" : "Modelling of Ceramic Particle Motion during Semi-Solid Forming of Aluminium Matrix Composites via CFD-DEM Four-Way Coupling", "user" : "roberta.toscano", "description" : "", "date" : "2023-09-04 11:41:55", "changeDate" : "2023-09-13 14:11:46", "count" : 3, "pub-type": "article", "journal": "Key Engineering Materials", "year": "2022", "url": "https://www.scientific.net/KEM.926.2303", "author": [ "Marco Speth","Johannes Heine","Kim Rouven Riedmüller","Mathias Liewald" ], "authors": [ {"first" : "Marco", "last" : "Speth"}, {"first" : "Johannes", "last" : "Heine"}, {"first" : "Kim Rouven", "last" : "Riedmüller"}, {"first" : "Mathias", "last" : "Liewald"} ], "volume": "926","pages": "2303--2311","abstract": "Today, aluminium matrix composites (AMC) are widely used for the manufacturing of lightweight, yet highly stressed components in automotive, aeronautic and electrical engineering. In order to achieve particle distributions as homogeneous as possible within these component's volumes and thus ensure optimum component properties, efforts are being made to simulate the manufacturing process prior to production. In this paper, AMC with extremely high particle fractions of more than 25 vol.\\% are considered in particular, as their processing still poses significant technological challenges. To model the particle motion in a computational fluid dynamics (CFD) simulation of the semi-solid forming process of this type of materials, a Lagrangian multiphase approach combining CFD and discrete element method (DEM) was used. Here, the DEM allowed all particle-particle interactions to be considered. Thus, different parameters influencing particle agglomeration, particle distribution as well as particle interaction with the cavity can be investigated during a numerical study. More specifically, the influence particle parameters such as cohesion forces and the influence of the forming speed onto the particle distribution in the final component ́s volume was analysed. The simulations were performed for a symmetric disc geometry. A forming tool was already available for this geometry, with which components could be manufactured to validate the simulation results. In the end, the study shows that by using four-way CFD-DEM coupling, simulation predictability for the semi-solid forming process of AMC could be significantly improved.", "issn" : "1662-9795", "doi" : "10.4028/p-xz23in", "bibtexKey": "Speth2022" } , { "type" : "Publication", "id" : "https://puma.ub.uni-stuttgart.de/bibtex/2881c58fe14338e4393d7e9436931e3b9/roberta.toscano", "tags" : [ "(AMC),Coefficient","(COV),High","Al-SiC,Aluminium","Variance","composites","composites,amc,coefficient","loading,Powder","loading,powder","matrix","mixing","mixing,al-sic,aluminium","of","particle","variance,high" ], "intraHash" : "881c58fe14338e4393d7e9436931e3b9", "interHash" : "998fa0b744d34a0c7f11cb41b474891f", "label" : "Study on mixing behaviour of aluminium-ceramic powder having high SiC volume fractions up to 50 vol.\\%", "user" : "roberta.toscano", "description" : "", "date" : "2023-09-04 11:41:55", "changeDate" : "2023-09-13 14:11:46", "count" : 4, "pub-type": "article", "journal": "Functional Composite Materials","publisher":"Springer International Publishing", "year": "2023", "url": "https://doi.org/10.1186/s42252-023-00045-z https://functionalcompositematerials.springeropen.com/articles/10.1186/s42252-023-00045-z", "author": [ "Marco Speth","Kim Rouven Riedmueller","Mathias Liewald" ], "authors": [ {"first" : "Marco", "last" : "Speth"}, {"first" : "Kim Rouven", "last" : "Riedmueller"}, {"first" : "Mathias", "last" : "Liewald"} ], "volume": "4","number": "1","pages": "8","abstract": "Aluminium matrix composites (AMC) do combine a high lightweight potential with a wide range of specific mechanical or thermal properties, depending on their material composition or the content of reinforcement particles, respectively. Currently, the three main production technologies for manufacturing such AMC are powder metallurgy, semi-solid processes and casting. Here, the AMC´s reinforcement proportion that can be processed depends on the chosen manufacturing strategy and is therefore often limited to a maximum value of 30 vol. \\%, due to agglomeration and porosity problems. In this context, the main objective is to understand the fundamental mixing behaviour of powder mixtures for AMC green body production having reinforcement contents of up to 50 vol.\\% SiC p . For this purpose, powder mixtures of monomodal AlSi7Mg0.6 and different SiC p fractions were prepared with different mixing times and speeds to investigate the influence of these mixing parameters on the homogeneity of the particle distribution. Afterwards, the influence of powder size on the mixing process was investigated. The results showed that a slower mixing speed resulted in faster homogenisation as well as a larger particle size can be faster mixed. Furthermore, a regression model was developed using mixing time, speed and particle loading, to determine sufficient mixing parameters.", "issn" : "2522-5774", "doi" : "10.1186/s42252-023-00045-z", "bibtexKey": "Speth2023a" } , { "type" : "Publication", "id" : "https://puma.ub.uni-stuttgart.de/bibtex/208be7563b587190c24a78304dab29287/mathematik", "tags" : [ "Discrete","Dynamic","Finite","Fracture","Moving-mesh","Two-phase","algorithm","am","aperture","flow","fracture","from:brittalenz","ians","in","matrix","media","methods","models","porous","propagation","volume" ], "intraHash" : "08be7563b587190c24a78304dab29287", "interHash" : "1ef19dc47df248ebcee76f8655d00172", "label" : "A finite-volume moving-mesh method for two-phase flow in\r\nfracturing porous media", "user" : "mathematik", "description" : "", "date" : "2022-02-23 10:11:48", "changeDate" : "2022-04-11 06:45:24", "count" : 4, "pub-type": "article", "journal": "J. Comput. Phys.", "year": "2022", "url": "https://www.sciencedirect.com/science/article/pii/S0021999122000936", "author": [ "Samuel Burbulla","Christian Rohde" ], "authors": [ {"first" : "Samuel", "last" : "Burbulla"}, {"first" : "Christian", "last" : "Rohde"} ], "pages": "111031","abstract": "Multiphase flow in fractured porous media can be described\r\nby discrete fracture matrix models that represent the fractures as\r\ndimensionally reduced manifolds embedded in the bulk porous medium.\r\nGeneralizing earlier work on this approach we focus on immiscible\r\ntwo-phase flow in time-dependent fracture geometries, i.e., the fracture\r\nitself and the aperture of the fractures might evolve in time. For\r\ndynamic fracture geometries of that kind, neglecting capillary forces,\r\nwe deduce by transversal averaging of a full dimensional description a\r\ndimensionally reduced model that governs the geometric evolution and the\r\nflow dynamics. The core computational contribution is a\r\nmixed-dimensional finite-volume discretization based on a conforming\r\nmoving-mesh ansatz. This finite-volume moving-mesh (FVMM) algorithm is\r\ntracking the fractures' motions as a family of unions of facets of the\r\nmesh. Notably, the method permits arbitrary movement of facets of the\r\ntriangulation while keeping the mass conservation constraint. In a\r\nseries of numerical examples we investigate the modeling error of the\r\nreduced model as it compares to the original full dimensional model.\r\nMoreover, we show the performance of the finite-volume moving-mesh\r\nalgorithm for the complex wave pattern that is induced by the\r\ninteraction of saturation fronts and evolving fractures.", "doi" : "https://doi.org/10.1016/j.jcp.2022.111031", "bibtexKey": "burbulla2022finitevolume" } , { "type" : "Publication", "id" : "https://puma.ub.uni-stuttgart.de/bibtex/2b9e0ef26b3072dde1659125d18d60b7c/carsten.scherer", "tags" : [ "EXC310","approach","dependent","functions","imng","inequality","lyapunov","matrix","optimization","peerReviewed","pn4","programs","relaxations" ], "intraHash" : "b9e0ef26b3072dde1659125d18d60b7c", "interHash" : "65da870d0bca9e82e2d000989caf405c", "label" : "Robust $l_1$ performance analysis for linear systems with parametric uncertainties", "user" : "carsten.scherer", "description" : "", "date" : "2021-12-07 20:40:52", "changeDate" : "2021-12-07 19:40:52", "count" : 4, "pub-type": "article", "journal": "Int. J. Control", "year": "2008", "url": "https://doi.org/10.1080/00207170701730451", "author": [ "J. M. Rieber","C. W. Scherer","F. Allgower" ], "authors": [ {"first" : "J. M.", "last" : "Rieber"}, {"first" : "C. W.", "last" : "Scherer"}, {"first" : "F.", "last" : "Allgower"} ], "volume": "81","number": "5","pages": "851-864","abstract": "In this contribution, a computational approach for analysing the robust e.-gain (or the robust l(1) performance) of uncertain linear systems is developed. In particular, the system's state-space matrices may have a rational dependence on structured parametric time-invariant or time-varying uncertainties. The computation is based on robust semi-definite programming and provides a trade-off between accuracy and computational effort. A novel matrix inequality condition to determine the star-norm of discrete-time systems is derived as an auxiliary result.", "shorttitle" : "Robust l(1) performance analysis for linear systems with parametric uncertainties", "file" : "://000255553000012", "endnotereftype" : "Journal Article", "bibtexKey": "RieSch08a" } , { "type" : "Publication", "id" : "https://puma.ub.uni-stuttgart.de/bibtex/250eb44f91950357cf988eb9394027e14/carsten.scherer", "tags" : [ "algorithms","bilinear","control","design","dynamic","feasibility","formulas","global","h-2","h-infinity","imng","inequalities","linear-systems","lmis","matrix","multiobjective","optimization","order","output-feedback","parameter","peerReviewed","robust","structured","synthesis","uncertainty" ], "intraHash" : "50eb44f91950357cf988eb9394027e14", "interHash" : "79b43995f394ecc9dbf6ddc0aa390ca5", "label" : "Robust output-feedback controller design via local BMI optimization", "user" : "carsten.scherer", "description" : "", "date" : "2021-12-07 20:40:52", "changeDate" : "2021-12-07 19:40:52", "count" : 4, "pub-type": "article", "journal": "Automatica", "year": "2004", "url": "https://doi.org/10.1016/j.automatica.2004.01.028", "author": [ "S. Kanev","C. W. Scherer","M. Verhaegen","B. De Schutter" ], "authors": [ {"first" : "S.", "last" : "Kanev"}, {"first" : "C. W.", "last" : "Scherer"}, {"first" : "M.", "last" : "Verhaegen"}, {"first" : "B.", "last" : "De Schutter"} ], "volume": "40","number": "7","pages": "1115-1127","abstract": "The problem of designing a globally optimal full-order output-feedback controller for polytopic uncertain systems is known to be a non-convex NP-hard optimization problem, that can be represented as a bilinear matrix inequality optimization problem for most design objectives. In this paper a new approach is proposed to the design of locally optimal controllers. It is iterative by nature, and starting from any initial feasible controller it performs local optimization over a suitably defined non-convex function at each iteration. The approach features the properties of computational efficiency, guaranteed convergence to a local optimum, and applicability to a very wide range of problems. Furthermore, a fast (but conservative) LMI-based procedure for computing an initially feasible controller is also presented. The complete approach is demonstrated on a model of one joint of a real-life space robotic manipulator. (C) 2004 Elsevier Ltd. All rights reserved.", "shorttitle" : "Robust output-feedback controller design via local BMI optimization", "file" : "://000221904200002", "issn" : "0005-1098", "endnotereftype" : "Journal Article", "bibtexKey": "KanSch04a" } , { "type" : "Publication", "id" : "https://puma.ub.uni-stuttgart.de/bibtex/250eb44f91950357cf988eb9394027e14/mathematik", "tags" : [ "robust","multiobjective","synthesis","control","imng","feasibility","bilinear","h-infinity","inequalities","algorithms","formulas","linear-systems","global","h-2","matrix","uncertainty","output-feedback","from:carsten.scherer","design","optimization","parameter","peerReviewed","lmis","structured","dynamic","order" ], "intraHash" : "50eb44f91950357cf988eb9394027e14", "interHash" : "79b43995f394ecc9dbf6ddc0aa390ca5", "label" : "Robust output-feedback controller design via local BMI optimization", "user" : "mathematik", "description" : "", "date" : "2021-12-01 21:53:35", "changeDate" : "2024-03-12 10:23:32", "count" : 4, "pub-type": "article", "journal": "Automatica", "year": "2004", "url": "https://doi.org/10.1016/j.automatica.2004.01.028", "author": [ "S. Kanev","C. W. Scherer","M. Verhaegen","B. De Schutter" ], "authors": [ {"first" : "S.", "last" : "Kanev"}, {"first" : "C. W.", "last" : "Scherer"}, {"first" : "M.", "last" : "Verhaegen"}, {"first" : "B.", "last" : "De Schutter"} ], "volume": "40","number": "7","pages": "1115-1127","abstract": "The problem of designing a globally optimal full-order output-feedback controller for polytopic uncertain systems is known to be a non-convex NP-hard optimization problem, that can be represented as a bilinear matrix inequality optimization problem for most design objectives. In this paper a new approach is proposed to the design of locally optimal controllers. It is iterative by nature, and starting from any initial feasible controller it performs local optimization over a suitably defined non-convex function at each iteration. The approach features the properties of computational efficiency, guaranteed convergence to a local optimum, and applicability to a very wide range of problems. Furthermore, a fast (but conservative) LMI-based procedure for computing an initially feasible controller is also presented. The complete approach is demonstrated on a model of one joint of a real-life space robotic manipulator. (C) 2004 Elsevier Ltd. All rights reserved.", "shorttitle" : "Robust output-feedback controller design via local BMI optimization", "file" : "://000221904200002", "issn" : "0005-1098", "endnotereftype" : "Journal Article", "bibtexKey": "KanSch04a" } , { "type" : "Publication", "id" : "https://puma.ub.uni-stuttgart.de/bibtex/2b9e0ef26b3072dde1659125d18d60b7c/mathematik", "tags" : [ "approach","lyapunov","functions","relaxations","imng","matrix","inequality","from:carsten.scherer","EXC310","optimization","pn4","peerReviewed","programs","dependent" ], "intraHash" : "b9e0ef26b3072dde1659125d18d60b7c", "interHash" : "65da870d0bca9e82e2d000989caf405c", "label" : "Robust $l_1$ performance analysis for linear systems with parametric uncertainties", "user" : "mathematik", "description" : "", "date" : "2021-12-01 20:49:49", "changeDate" : "2024-03-12 10:23:53", "count" : 4, "pub-type": "article", "journal": "Int. J. Control", "year": "2008", "url": "https://doi.org/10.1080/00207170701730451", "author": [ "J. M. Rieber","C. W. Scherer","F. Allgower" ], "authors": [ {"first" : "J. M.", "last" : "Rieber"}, {"first" : "C. W.", "last" : "Scherer"}, {"first" : "F.", "last" : "Allgower"} ], "volume": "81","number": "5","pages": "851-864","abstract": "In this contribution, a computational approach for analysing the robust e.-gain (or the robust l(1) performance) of uncertain linear systems is developed. In particular, the system's state-space matrices may have a rational dependence on structured parametric time-invariant or time-varying uncertainties. The computation is based on robust semi-definite programming and provides a trade-off between accuracy and computational effort. A novel matrix inequality condition to determine the star-norm of discrete-time systems is derived as an auxiliary result.", "shorttitle" : "Robust l(1) performance analysis for linear systems with parametric uncertainties", "file" : "://000255553000012", "issn" : "0020-7179", "endnotereftype" : "Journal Article", "bibtexKey": "RieSch08a" } , { "type" : "Publication", "id" : "https://puma.ub.uni-stuttgart.de/bibtex/2798e2e62bd35092139fcd4b84f7ec2e5/mathematik", "tags" : [ "linear","robust","quadratic","rates","control","imng","rejection","pn4","parameters","disturbance","inequalities","stabilization","convexity","matrix","constraints","feedback","integral","output","systems","(lmis)","from:tobiasholicki","EXC310","optimization","(iqcs)","peerReviewed" ], "intraHash" : "798e2e62bd35092139fcd4b84f7ec2e5", "interHash" : "935b7ffc617413001028ab65b89dfb4d", "label" : "Robust output feedback control against disturbance filter uncertainty described by dynamic integral quadratic constraints", "user" : "mathematik", "description" : "", "date" : "2021-06-16 14:14:26", "changeDate" : "2024-03-12 10:23:40", "count" : 7, "pub-type": "article", "journal": "Int. J. Robust Nonlin.", "year": "2010", "url": "https://doi.org/10.1002/rnc.1554", "author": [ "S. G. Dietz","C. W. Scherer" ], "authors": [ {"first" : "S. G.", "last" : "Dietz"}, {"first" : "C. W.", "last" : "Scherer"} ], "volume": "20","number": "17","pages": "1903-1919","abstract": "Motivated by a robust disturbance rejection problem, in which disturbances are described by an uncertain filter at the plant input, a convex solution is presented for the robust output feedback controller synthesis problem for a particularly structured plant. The uncertainties are characterized by an integral quadratic constraint (IQC) with general frequency-dependent multipliers. By exploiting the structure of the generalized plant, linear matrix inequality (LMI)-synthesis conditions are derived in order to guarantee a specified L(2)-gain or H(2)-norm performance level, provided that the IQC multipliers are described by LMI constraints. Moreover, it is shown that part of the controller variables can be eliminated. Finally, the rejection of non-stationary sinusoidal disturbance signals is considered. In a numerical example, it is shown that specifying a bound on the rate-of-variation of the time-varying frequency can improve the performance if compared with the static IQC multipliers. Copyright (C) 2009 John Wiley & Sons, Ltd.", "shorttitle" : "Robust output feedback control against disturbance filter uncertainty described by dynamic integral quadratic constraints", "file" : "://000284215900001:Djvu", "issn" : "1049-8923", "endnotereftype" : "Journal Article", "bibtexKey": "DieSch10" } , { "type" : "Publication", "id" : "https://puma.ub.uni-stuttgart.de/bibtex/2b56731ba0d7a47a83512585f4d04d49c/isw-bibliothek", "tags" : [ "isw-2018","matrix","xwk" ], "intraHash" : "b56731ba0d7a47a83512585f4d04d49c", "interHash" : "12ce43fe5666924223a64e637d077811", "label" : "Formschlüssiges Spannen leicht gemacht", "user" : "isw-bibliothek", "description" : "", "date" : "2019-12-03 10:06:10", "changeDate" : "2019-12-03 09:58:30", "count" : 1, "pub-type": "article", "journal": "KEM Konstruktion", "year": "2018", "url": "", "author": [ "Markus Wnuk","Armin Lechler","Alexander Verl" ], "authors": [ {"first" : "Markus", "last" : "Wnuk"}, {"first" : "Armin", "last" : "Lechler"}, {"first" : "Alexander", "last" : "Verl"} ], "editor": [ "Corban Michael" ], "editors": [ {"first" : "Corban", "last" : "Michael"} ], "number": "12","pages": "34-35", "bibtexKey": "wnuk2018formschlssiges" } , { "type" : "Publication", "id" : "https://puma.ub.uni-stuttgart.de/bibtex/270cd658f5aeddea66235eee1a073bec1/mgeiger", "tags" : [ "Actuators,","Controllability,","Damping,","Eigenvalues","Gramian,","Gramian-based","Mathematical","Measurement,","Optimization,","active","actuator","actuators,","adaptive","algebra,","and","control","control,","controllability","controllability,","criterion,","damping,","eigenfunctions,","engineering","external","externally","high-rise","induced","loads,","matrix","model,","models,","modes","modification,","optimal","optimisation,","optimization","order","placement,","reduced","reduction,","response","spillover","spillover,","structure,","structures,","supports,","systems,","truss","vibration","vibrations," ], "intraHash" : "70cd658f5aeddea66235eee1a073bec1", "interHash" : "53ad49f8e25468c63611b703749d7cd3", "label" : "Gramian-based actuator placement with spillover reduction for active damping of adaptive structures", "user" : "mgeiger", "description" : "", "date" : "2019-11-08 16:11:00", "changeDate" : "2019-11-08 15:14:53", "count" : 5, "pub-type": "inproceedings", "booktitle": "2017 IEEE International Conference on Advanced Intelligent Mechatronics (AIM), July 3-7, 2017, Munich", "year": "2017", "url": "", "author": [ "Michael Heidingsfeld","Philipp Rapp","Michael Böhm","Oliver Sawodny" ], "authors": [ {"first" : "Michael", "last" : "Heidingsfeld"}, {"first" : "Philipp", "last" : "Rapp"}, {"first" : "Michael", "last" : "Böhm"}, {"first" : "Oliver", "last" : "Sawodny"} ], "pages": "904--909","abstract": "Adaptive structures are engineering structures with the ability to modify their response to external loads. This includes active damping of externally induced vibrations. The controller design is usually based on reduced order models that comprise the most important vibration modes of the structure. This can lead to unwanted excitation of the neglected modes, known as control spillover. One means to cope with this problem is by proper placement of the actuators. In this contribution, we present a method for optimal actuator placement for active damping of adaptive structures that explicitly considers spillover effects by optimizing the trade-off between controllability of the considered and neglected modes. The optimization criterion is based on the controllability Gramian. Under certain conditions, the globally optimal solution can be found. The proposed method is applied to a numerical example of a high-rise truss structure.", "doi" : "10.1109/AIM.2017.8014133", "bibtexKey": "heidingsfeld_gramian-based_2017" } , { "type" : "Publication", "id" : "https://puma.ub.uni-stuttgart.de/bibtex/2b881c5bd45bba967a418431f264925f3/mathematik", "tags" : [ "15A23;","41A05;","42A82;","65Y20","Fast","Interpolation;","Matrix","Positive","computation;","definite","factorization;","from:mhartmann","functions;","ians","vorlaeufig" ], "intraHash" : "b881c5bd45bba967a418431f264925f3", "interHash" : "5fc476059e77e8e9226f6a15761cf6a5", "label" : "Fast computation of orthonormal basis for RBF spaces through Krylov\n\tspace methods", "user" : "mathematik", "description" : "", "date" : "2018-07-20 10:54:28", "changeDate" : "2019-12-18 14:37:55", "count" : 4, "pub-type": "article", "journal": "BIT Numerical Mathematics","publisher":"Springer Netherlands", "year": "2015", "url": "http://dx.doi.org/10.1007/s10543-014-0537-6", "author": [ "Stefano De Marchi","Gabriele Santin" ], "authors": [ {"first" : "Stefano", "last" : "De Marchi"}, {"first" : "Gabriele", "last" : "Santin"} ], "volume": "55","number": "4","pages": "949--966","abstract": "In recent years, in the setting of radial basis function, the study\n\tof approximation algorithms has particularly focused on the construction\n\tof (stable) bases for the associated Hilbert spaces. One of the ways\n\tof describing such spaces and their properties is the study of a\n\tparticular integral operator and its spectrum. We proposed in a recent\n\twork the so-called WSVD basis, which is strictly connected to the\n\teigen-decomposition of this operator and allows to overcome some\n\tproblems related to the stability of the computation of the approximant\n\tfor a wide class of radial kernels. Although effective, this basis\n\tis computationally expensive to compute. In this paper we discuss\n\ta method to improve and compute in a fast way the basis using methods\n\trelated to Krylov subspaces. After reviewing the connections between\n\tthe two bases, we concentrate on the properties of the new one, describing\n\tits behavior by numerical tests.", "issn" : "0006-3835", "file" : ":http\\://www.mathematik.uni-stuttgart.de/fak8/ians/publications/files/DeMSa2015_www_Fast_computation_onb_RBF.pdf:PDF", "owner" : "santinge", "language" : "English", "doi" : "10.1007/s10543-014-0537-6", "bibtexKey": "demarchi2015computation" } , { "type" : "Publication", "id" : "https://puma.ub.uni-stuttgart.de/bibtex/2b881c5bd45bba967a418431f264925f3/mhartmann", "tags" : [ "15A23;","41A05;","42A82;","65Y20","Fast","Interpolation;","Matrix","Positive","computation;","definite","factorization;","functions;","vorlaeufig" ], "intraHash" : "b881c5bd45bba967a418431f264925f3", "interHash" : "5fc476059e77e8e9226f6a15761cf6a5", "label" : "Fast computation of orthonormal basis for RBF spaces through Krylov\n\tspace methods", "user" : "mhartmann", "description" : "", "date" : "2018-07-20 10:54:15", "changeDate" : "2018-07-20 08:54:15", "count" : 4, "pub-type": "article", "journal": "BIT Numerical Mathematics","publisher":"Springer Netherlands", "year": "2015", "url": "http://dx.doi.org/10.1007/s10543-014-0537-6", "author": [ "Stefano De Marchi","Gabriele Santin" ], "authors": [ {"first" : "Stefano", "last" : "De Marchi"}, {"first" : "Gabriele", "last" : "Santin"} ], "volume": "55","number": "4","pages": "949--966","abstract": "In recent years, in the setting of radial basis function, the study\n\tof approximation algorithms has particularly focused on the construction\n\tof (stable) bases for the associated Hilbert spaces. One of the ways\n\tof describing such spaces and their properties is the study of a\n\tparticular integral operator and its spectrum. We proposed in a recent\n\twork the so-called WSVD basis, which is strictly connected to the\n\teigen-decomposition of this operator and allows to overcome some\n\tproblems related to the stability of the computation of the approximant\n\tfor a wide class of radial kernels. Although effective, this basis\n\tis computationally expensive to compute. In this paper we discuss\n\ta method to improve and compute in a fast way the basis using methods\n\trelated to Krylov subspaces. After reviewing the connections between\n\tthe two bases, we concentrate on the properties of the new one, describing\n\tits behavior by numerical tests.", "issn" : "0006-3835", "file" : ":http\\://www.mathematik.uni-stuttgart.de/fak8/ians/publications/files/DeMSa2015_www_Fast_computation_onb_RBF.pdf:PDF", "owner" : "santinge", "language" : "English", "doi" : "10.1007/s10543-014-0537-6", "bibtexKey": "demarchi2015computation" } , { "type" : "Publication", "id" : "https://puma.ub.uni-stuttgart.de/bibtex/2a6dcd392b900956871dd3cfde89cd481/clausbraun", "tags" : [ "ABFT","GPGPU","GPU","SimTech","adaptivity","algebra","algorithm-based","autonompous","error","error-correction","error-detection","fault-tolerance","linear","matrix","matrix-multiplication","metric","myown","rounding","rounding-error" ], "intraHash" : "a6dcd392b900956871dd3cfde89cd481", "interHash" : "f672f35af5f6b825bda005ca703be294", "label" : "A-ABFT: Autonomous Algorithm-Based Fault Tolerance for Matrix Multiplications on Graphics Processing Units", "user" : "clausbraun", "description" : "", "date" : "2018-03-19 16:15:07", "changeDate" : "2018-03-19 15:37:08", "count" : 7, "pub-type": "inproceedings", "booktitle": "Proceedings of the 44th Annual IEEE/IFIP International Conference on Dependable Systems and Networks (DSN'14)", "year": "2014", "url": "", "author": [ "Claus Braun","Sebastian Halder","Hans-Joachim Wunderlich" ], "authors": [ {"first" : "Claus", "last" : "Braun"}, {"first" : "Sebastian", "last" : "Halder"}, {"first" : "Hans-Joachim", "last" : "Wunderlich"} ], "pages": "443--454","abstract": "Graphics processing units (GPUs) enable large-scale scientific applications and simulations on the desktop. To allow scientific computing on GPUs with high performance and reliability requirements, the application of software-based fault tolerance is attractive. Algorithm-Based Fault Tolerance (ABFT) protects important scientific operations like matrix multiplications. However, the application to floating-point operations necessitates the runtime classification of errors into inevitable rounding errors, allowed compute errors in the magnitude of such rounding errors, and into critical errors that are larger than those and not tolerable. Hence, an ABFT scheme needs suitable rounding error bounds to detect errors reliably. The determination of such error bounds is a highly challenging task, especially since it has to be integrated tightly into the algorithm and executed autonomously with low performance overhead.\r\n In this work, A-ABFT for matrix multiplications on GPUs is introduced, which is a new, parallel ABFT scheme that determines rounding error bounds autonomously at runtime with low performance overhead and high error coverage.", "file" : "http://www.iti.uni-stuttgart.de/fileadmin/rami/files/publications/2014/DSN_BraunHH2014.pdf", "doi" : "http://dx.doi.org/10.1109/DSN.2014.48", "bibtexKey": "BraunHW2014" } , { "type" : "Publication", "id" : "https://puma.ub.uni-stuttgart.de/bibtex/2cb73d441bfa74c53f7f794b50d54b947/ulrikeoffenbeck", "tags" : [ "Mueller","depolarization","matrix" ], "intraHash" : "cb73d441bfa74c53f7f794b50d54b947", "interHash" : "f7dae90cd791616bef5a3441e46bfaa4", "label" : "Depolarization of a randomly distributed plasmonic meander metasurface characterized by Mueller matrix spectroscopic ellipsometry", "user" : "ulrikeoffenbeck", "description" : "", "date" : "2018-01-30 08:19:30", "changeDate" : "2018-03-08 14:22:50", "count" : 7, "pub-type": "article", "journal": "Opt. Express","publisher":"OSA", "year": "2016", "url": "http://www.opticsexpress.org/abstract.cfm?URI=oe-24-24-28056", "author": [ "Liwei Fu","Audrey Berrier","Huiyu Li","Philipp Schau","Karsten Frenner","Martin Dressel","Wolfgang Osten" ], "authors": [ {"first" : "Liwei", "last" : "Fu"}, {"first" : "Audrey", "last" : "Berrier"}, {"first" : "Huiyu", "last" : "Li"}, {"first" : "Philipp", "last" : "Schau"}, {"first" : "Karsten", "last" : "Frenner"}, {"first" : "Martin", "last" : "Dressel"}, {"first" : "Wolfgang", "last" : "Osten"} ], "volume": "24","number": "24","pages": "28056-28064","abstract": "Metallic nanostructures offer efficient solutions in polarization control with a very low thickness. In this report, we investigate the optical properties of a nano-fabricated plasmonic pseudo-depolarizer using Mueller matrix spectroscopic ellipsometry in transmission configuration. The depolarizer is composed of 256 square cells, each containing a periodically corrugated metallic film with random orientation. The full Mueller matrix was analyzed as a function of incident angle in a range between 0 and 20° and over the whole rotation angle range. Depolarization could be achieved in two visible wavelength regions around the short-range and long-range surface plasmon polariton frequencies, respectively. Furthermore, depolarization for circularly polarized light was 2.5 times stronger than that for linearly polarized light. Our results could work as a guidance for realizing a broadband high efficiency dielectric metasurface depolarizers.", "doi" : "10.1364/OE.24.028056", "bibtexKey": "Fu:16" } , { "type" : "Publication", "id" : "https://puma.ub.uni-stuttgart.de/bibtex/2fab52e286cc84be7de29f92194abdde2/ulrikeoffenbeck", "tags" : [ "Mueller","matrix" ], "intraHash" : "fab52e286cc84be7de29f92194abdde2", "interHash" : "95f9994b7dd3e989405a70a126f2258d", "label" : "Physical interpretation of Mueller matrix spectra: a versatile method applied to gold gratings", "user" : "ulrikeoffenbeck", "description" : "", "date" : "2018-01-29 14:16:37", "changeDate" : "2018-05-15 07:55:33", "count" : 1, "pub-type": "article", "journal": "Opt. Express","publisher":"OSA", "year": "2017", "url": "http://www.opticsexpress.org/abstract.cfm?URI=oe-25-6-6983", "author": [ "Meng Wang","Anja Loehle","Bruno Gompf","Martin Dressel","Audrey Berrier" ], "authors": [ {"first" : "Meng", "last" : "Wang"}, {"first" : "Anja", "last" : "Loehle"}, {"first" : "Bruno", "last" : "Gompf"}, {"first" : "Martin", "last" : "Dressel"}, {"first" : "Audrey", "last" : "Berrier"} ], "volume": "25","number": "6","pages": "6983-6996","abstract": "The interaction of nanostructures, periodic or random, with polarized light creates very rich physics where scattering, diffraction and absorbance are linked to a variety of dispersive modes and coupling effects. Each of these excitations depends strongly on polarization, angle of incidence, azimuthal orientation of the sample and wavelength. The entire optical response can be obtained, independently from any model, by measuring the Mueller matrices at various k-vectors over a broad frequency range. This results in complex data hiding the underlying physics. Here we present a simple but versatile method to identify the physical properties present in the Mueller matrices. This method is applicable to a wide variety of photonic and plasmonic samples. Based on the simple example of a one-dimensional gold grating where the optical response is characterized not only by diffraction but also by a complex mixing of polarization, we present a very general procedure to analyze the Mueller matrix data using simple analytical tools. The calculated Mueller matrix contour plots obtained from an effective anisotropic layer model are completed by the presence of plasmonic modes, Rayleigh-Woods anomalies and the interband transition absorbance. A comparison of the so-constructed contour plots with the measured ones satisfactorily connects the optical properties of the grating to their physical origin. This straightforward procedure is very general and will be powerful for the analysis of complex optical nanostructures.", "doi" : "10.1364/OE.25.006983", "bibtexKey": "Wang:17" } , { "type" : "Publication", "id" : "https://puma.ub.uni-stuttgart.de/bibtex/244473238540dedd53d2e041254efc1e8/ulrikeoffenbeck", "tags" : [ "MR-1","dielectric","extracellular","matrix","universalities" ], "intraHash" : "44473238540dedd53d2e041254efc1e8", "interHash" : "c6cbdb461d4c99336bc4e09cbfde2ccb", "label" : "Observation of dielectric universalities in albumin, cytochrome C and Shewanella oneidensis MR-1 extracellular matrix", "user" : "ulrikeoffenbeck", "description" : "", "date" : "2018-01-26 14:53:24", "changeDate" : "2018-03-08 14:08:19", "count" : 1, "pub-type": "article", "journal": "Scientific Reports", "year": "2017", "url": "https://doi.org/10.1038/s41598-017-15693-y", "author": [ "K. A. Motovilov","M. Savinov","E. S. Zhukova","A. A. Pronin","Z. V. Gagkaeva","V. Grinenko","K. V. Sidoruk","T. A. Voeikova","P. Yu Barzilovich","A. K. Grebenko","S. V. Lisovskii","V. I. Torgashev","P. Bednyakov","J. Pokorný","M. Dressel","B. P. Gorshunov" ], "authors": [ {"first" : "K. A.", "last" : "Motovilov"}, {"first" : "M.", "last" : "Savinov"}, {"first" : "E. S.", "last" : "Zhukova"}, {"first" : "A. A.", "last" : "Pronin"}, {"first" : "Z. V.", "last" : "Gagkaeva"}, {"first" : "V.", "last" : "Grinenko"}, {"first" : "K. V.", "last" : "Sidoruk"}, {"first" : "T. A.", "last" : "Voeikova"}, {"first" : "P. Yu", "last" : "Barzilovich"}, {"first" : "A. K.", "last" : "Grebenko"}, {"first" : "S. V.", "last" : "Lisovskii"}, {"first" : "V. I.", "last" : "Torgashev"}, {"first" : "P.", "last" : "Bednyakov"}, {"first" : "J.", "last" : "Pokorný"}, {"first" : "M.", "last" : "Dressel"}, {"first" : "B. P.", "last" : "Gorshunov"} ], "volume": "7","number": "1","pages": "15731--","abstract": "The electrodynamics of metals is well understood within the Drude conductivity model; properties of insulators and semiconductors are governed by a gap in the electronic states. But there is a great variety of disordered materials that do not fall in these categories and still respond to external field in an amazingly uniform manner. At radiofrequencies delocalized charges yield a frequency-independent conductivity σ 1(ν) whose magnitude exponentially decreases while cooling. With increasing frequency, dispersionless conductivity starts to reveal a power-law dependence σ 1(ν)∝ν s with s\u2009<\u20091 caused by hopping charge carriers. At low temperatures, such Universal Dielectric Response can cross over to another universal regime with nearly constant loss ε\u2033∝σ1/ν\u2009=\u2009const. The powerful research potential based on such universalities is widely used in condensed matter physics. Here we study the broad-band (1\u20131012\u2009Hz) dielectric response of Shewanella oneidensis MR-1 extracellular matrix, cytochrome C and serum albumin. Applying concepts of condensed matter physics, we identify transport mechanisms and a number of energy, time, frequency, spatial and temperature scales in these biological objects, which can provide us with deeper insight into the protein dynamics.", "issn" : "20452322", "refid" : "Motovilov2017", "doi" : "10.1038/s41598-017-15693-y", "bibtexKey": "motovilov2017observation" } ] }