+publisher:"ETH Zürich" +contributor:("Herrmann, Hans J.")

ETH Zürich

1. Berger, Damian. Learning Capabilities and Robustness of Critical Neural Networks.

Degree: 2019, ETH Zürich

URL: http://hdl.handle.net/20.500.11850/341903

Subjects/Keywords: info:eu-repo/classification/ddc/4; info:eu-repo/classification/ddc/610; Data processing, computer science; Medical sciences, medicine

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APA (6^th Edition):

Berger, D. (2019). Learning Capabilities and Robustness of Critical Neural Networks. (Doctoral Dissertation). ETH Zürich. Retrieved from http://hdl.handle.net/20.500.11850/341903

Chicago Manual of Style (16^th Edition):

Berger, Damian. “Learning Capabilities and Robustness of Critical Neural Networks.” 2019. Doctoral Dissertation, ETH Zürich. Accessed April 13, 2021. http://hdl.handle.net/20.500.11850/341903.

MLA Handbook (7^th Edition):

Berger, Damian. “Learning Capabilities and Robustness of Critical Neural Networks.” 2019. Web. 13 Apr 2021.

Vancouver:

Berger D. Learning Capabilities and Robustness of Critical Neural Networks. [Internet] [Doctoral dissertation]. ETH Zürich; 2019. [cited 2021 Apr 13]. Available from: http://hdl.handle.net/20.500.11850/341903.

Council of Science Editors:

Berger D. Learning Capabilities and Robustness of Critical Neural Networks. [Doctoral Dissertation]. ETH Zürich; 2019. Available from: http://hdl.handle.net/20.500.11850/341903

ETH Zürich

2. Böttcher, Lucas. Epidemic processes.

Degree: 2018, ETH Zürich

URL: http://hdl.handle.net/20.500.11850/270037

► Various phenomena in our daily world exhibit similarities to epidemic spreading. Fashion or technical trends are referred to as viral when they reach a large… (more)

▼ Various phenomena in our daily world exhibit similarities to epidemic spreading. Fashion or technical trends are referred to as viral when they reach a large part of a society. In general, trends, opinions, diseases and failure in social or technical networks are characterized by the fact that they spread from an ``infected'' source to a ``non-infected'' state. We use the term epidemic process to refer to the described variety of different spreading phenomena. In addition to infection processes, external influences such as media in the case opinion spreading among people also play a major role. In contrast to a simple contagion, where one source is sufficient to sustain spreading, there also exist complex contagion phenomena where multiple sources are required. Social opinion formation is often described by the latter process. Until now, different spreading models have been developed and applied to account for different numbers of sources. We propose a general contagion model which accounts for both external influences and different numbers of ``infectious'' sources. We show that our contagion model exhibits a novel characteristic critical behavior which we describe using mathematical concepts that have their origin in catastrophe theory. Besides the stationary critical behavior, we also verify dynamical universal behavior by analyzing the corresponding correlation and response functions. The identification of universal critical behavior allows to demonstrate similarities between epidemic models that appear different at first sight. Based on those similarities, it is possible to classify spreading models. This way of classifying models is closely related to the study of phase transitions in statistical physics. Typically, one studies an order parameter (e.g. the number of infected) as a function of a control parameter (e.g. infection rate). In many situations, one finds a transition point or critical point of the control parameter at which the order parameter starts growing. At this point, there exists a characteristic behavior of the order parameter as a function of the control parameter. Considerations like these allow to apply methods from statistical physics which are important for describing phase transitions of percolation and magnetic systems. We consider different applications after defining and classifying our general modeling framework. We use the gained insights from the analysis of our general contagion model to propose a model for political campaigns. The suggested campaign model accounts for the complex interplay between activists, persuadables, political clout, budget and costs. Furthermore, we also study the opinion formation process in online petitions by applying different time series analysis methods. The last two examples have their origin in the field of disease spreading. We describe a very effective method of targeted recovery of infected individuals, which makes it possible to drastically reduce the number of infected cases. This protocol is also applicable to other spreading processes.… Advisors/Committee Members: Herrmann, Hans J., Helbing, Dirk.

Subjects/Keywords: Spreading; Bifurcations; Phase transitions and critical phenomena; Epidemic models; Opinion dynamics; Network theory; Mean-field theory; Universality; Ageing; Dynamical systems; Campaigns; Critical phenomena; Statistical physics; Simulation; Critical exponents; Cusp catastrophe; info:eu-repo/classification/ddc/510; info:eu-repo/classification/ddc/530; Mathematics; Physics

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Böttcher, L. (2018). Epidemic processes. (Doctoral Dissertation). ETH Zürich. Retrieved from http://hdl.handle.net/20.500.11850/270037

Chicago Manual of Style (16^th Edition):

Böttcher, Lucas. “Epidemic processes.” 2018. Doctoral Dissertation, ETH Zürich. Accessed April 13, 2021. http://hdl.handle.net/20.500.11850/270037.

MLA Handbook (7^th Edition):

Böttcher, Lucas. “Epidemic processes.” 2018. Web. 13 Apr 2021.

Vancouver:

Böttcher L. Epidemic processes. [Internet] [Doctoral dissertation]. ETH Zürich; 2018. [cited 2021 Apr 13]. Available from: http://hdl.handle.net/20.500.11850/270037.

Council of Science Editors:

Böttcher L. Epidemic processes. [Doctoral Dissertation]. ETH Zürich; 2018. Available from: http://hdl.handle.net/20.500.11850/270037

ETH Zürich

3. Iliev, Pavel. Mechanical Behavior of Confined Granular Materials.

Degree: 2019, ETH Zürich

URL: http://hdl.handle.net/20.500.11850/341577

Subjects/Keywords: info:eu-repo/classification/ddc/690; info:eu-repo/classification/ddc/620; Buildings; Engineering & allied operations

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Iliev, P. (2019). Mechanical Behavior of Confined Granular Materials. (Doctoral Dissertation). ETH Zürich. Retrieved from http://hdl.handle.net/20.500.11850/341577

Chicago Manual of Style (16^th Edition):

Iliev, Pavel. “Mechanical Behavior of Confined Granular Materials.” 2019. Doctoral Dissertation, ETH Zürich. Accessed April 13, 2021. http://hdl.handle.net/20.500.11850/341577.

MLA Handbook (7^th Edition):

Iliev, Pavel. “Mechanical Behavior of Confined Granular Materials.” 2019. Web. 13 Apr 2021.

Vancouver:

Iliev P. Mechanical Behavior of Confined Granular Materials. [Internet] [Doctoral dissertation]. ETH Zürich; 2019. [cited 2021 Apr 13]. Available from: http://hdl.handle.net/20.500.11850/341577.

Council of Science Editors:

Iliev P. Mechanical Behavior of Confined Granular Materials. [Doctoral Dissertation]. ETH Zürich; 2019. Available from: http://hdl.handle.net/20.500.11850/341577

ETH Zürich

4. Jäger, Robin. Erosion and Deposition in Porous Media.

Degree: 2018, ETH Zürich

URL: http://hdl.handle.net/20.500.11850/275695

► Suspension flow through porous media featuring deposition and erosion is a process that occurs in many areas and at different scales. Prominent examples include filtering… (more)

Subjects/Keywords: Fluid dynamics; Lattice Boltzmann model; Suspension; Porous media; info:eu-repo/classification/ddc/560; info:eu-repo/classification/ddc/530; Paleontology, paleozoology; Physics

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Jäger, R. (2018). Erosion and Deposition in Porous Media. (Doctoral Dissertation). ETH Zürich. Retrieved from http://hdl.handle.net/20.500.11850/275695

Chicago Manual of Style (16^th Edition):

Jäger, Robin. “Erosion and Deposition in Porous Media.” 2018. Doctoral Dissertation, ETH Zürich. Accessed April 13, 2021. http://hdl.handle.net/20.500.11850/275695.

MLA Handbook (7^th Edition):

Jäger, Robin. “Erosion and Deposition in Porous Media.” 2018. Web. 13 Apr 2021.

Vancouver:

Jäger R. Erosion and Deposition in Porous Media. [Internet] [Doctoral dissertation]. ETH Zürich; 2018. [cited 2021 Apr 13]. Available from: http://hdl.handle.net/20.500.11850/275695.

Council of Science Editors:

Jäger R. Erosion and Deposition in Porous Media. [Doctoral Dissertation]. ETH Zürich; 2018. Available from: http://hdl.handle.net/20.500.11850/275695

ETH Zürich

5. Lemrich, Laure. Discrete Element Modeling of Acoustic Wave Propagation in Granular Media: Nonlinearity and Material Softening.

Degree: 2019, ETH Zürich

URL: http://hdl.handle.net/20.500.11850/342965

► Granular media is one of the most common form of material which exists in many geophysical phenomena such as landslides and earthquakes. It is also… (more)

▼ Granular media is one of the most common form of material which exists in many geophysical phenomena such as landslides and earthquakes. It is also present in the industry for transport, storage, and for mixing processes. Constitutive equations are essential to predict and control granular media behavior, but they are not fully developed yet. In particular, the history of a granular packing has a determinant influence on the arrangement of its particles and the organization and nature of inter-particle contacts. The arrangement of particles and contacts in turn affects the material response to external perturbations such as compression, shear and wave propagation. This thesis studies the propagation of acoustic waves through the contact network. The Effective Medium Theory and continuum descriptions partially solve the constitutive equations of dense packings of granular media but cannot fully describe the phenomenon as the Effective Medium Theory models ensembles and continuum descriptions neglect particle rearrangements. Dynamic testing has shown a dependency of resonance frequency on strain at low strains in confined granular packings (Johnson and Jia 2005; Inserra et al. 2008) but this study has not been extended to high strains. We present a detailed study of dynamic testing in confined random packings of weakly polydisperse glass beads using the Discrete Element Method to measure the resonance frequency over a range of strains. We find a decrease in resonance frequency at high strain, called softening, that only depends on the normal component of the contact force, the coordination number and the average inter-particle overlap. The mean-field assumption of the Effective Medium Theory successfully predicts the dependency of softening on confining stress. The Effective Contact Theory is a model developed in this thesis to relate the breaking of contacts and decrease in coordination number to softening by defining a granular temperature based on kinetic energy. For the first time, granular temperature is used to model contact evolution rather than particle motion. The Effective Contact Theory successfully relate the probability of a contact breaking to softening in granular media. Simulations of wave propagation in static packings show an excellent agreement between wave velocity measured from direct wave propagation, dynamic testing and bulk and shear compression tests. Wave damping and distortion increases with amplitude and frequency and, at high frequency, waves are propagated through scattering and rapidly damped. Advisors/Committee Members: Herrmann, Hans J., Jia, Xiaoping.

Subjects/Keywords: Granular media; Condensed Matter Physics; wave propagation; Nonlinear phenomena; Effective field theories; effective contact theory; granular temperature; softening; Weakening; discrete element method; granular material; granular matter; Condensed matter; info:eu-repo/classification/ddc/530; Physics

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Lemrich, L. (2019). Discrete Element Modeling of Acoustic Wave Propagation in Granular Media: Nonlinearity and Material Softening. (Doctoral Dissertation). ETH Zürich. Retrieved from http://hdl.handle.net/20.500.11850/342965

Chicago Manual of Style (16^th Edition):

Lemrich, Laure. “Discrete Element Modeling of Acoustic Wave Propagation in Granular Media: Nonlinearity and Material Softening.” 2019. Doctoral Dissertation, ETH Zürich. Accessed April 13, 2021. http://hdl.handle.net/20.500.11850/342965.

MLA Handbook (7^th Edition):

Lemrich, Laure. “Discrete Element Modeling of Acoustic Wave Propagation in Granular Media: Nonlinearity and Material Softening.” 2019. Web. 13 Apr 2021.

Vancouver:

Lemrich L. Discrete Element Modeling of Acoustic Wave Propagation in Granular Media: Nonlinearity and Material Softening. [Internet] [Doctoral dissertation]. ETH Zürich; 2019. [cited 2021 Apr 13]. Available from: http://hdl.handle.net/20.500.11850/342965.

Council of Science Editors:

Lemrich L. Discrete Element Modeling of Acoustic Wave Propagation in Granular Media: Nonlinearity and Material Softening. [Doctoral Dissertation]. ETH Zürich; 2019. Available from: http://hdl.handle.net/20.500.11850/342965

6. Lorimer, Thomas. Optimal network structures and methods for computation.

Degree: 2017, ETH Zürich

URL: http://hdl.handle.net/20.500.11850/253730

Subjects/Keywords: info:eu-repo/classification/ddc/4; Data processing, computer science

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Lorimer, T. (2017). Optimal network structures and methods for computation. (Doctoral Dissertation). ETH Zürich. Retrieved from http://hdl.handle.net/20.500.11850/253730

Chicago Manual of Style (16^th Edition):

Lorimer, Thomas. “Optimal network structures and methods for computation.” 2017. Doctoral Dissertation, ETH Zürich. Accessed April 13, 2021. http://hdl.handle.net/20.500.11850/253730.

MLA Handbook (7^th Edition):

Lorimer, Thomas. “Optimal network structures and methods for computation.” 2017. Web. 13 Apr 2021.

Vancouver:

Lorimer T. Optimal network structures and methods for computation. [Internet] [Doctoral dissertation]. ETH Zürich; 2017. [cited 2021 Apr 13]. Available from: http://hdl.handle.net/20.500.11850/253730.

Council of Science Editors:

Lorimer T. Optimal network structures and methods for computation. [Doctoral Dissertation]. ETH Zürich; 2017. Available from: http://hdl.handle.net/20.500.11850/253730

ETH Zürich

7. Michiels Van Kessenich, Laurens. Critical Neural Networks and Pattern Recognition.

Degree: 2018, ETH Zürich

URL: http://hdl.handle.net/20.500.11850/277641

► How cortical systems self-organise and function is one of the great unresolved questions science currently faces. The combination of billions of neurons, each, by themselves,… (more)

▼ How cortical systems self-organise and function is one of the great unresolved questions science currently faces. The combination of billions of neurons, each, by themselves, relatively simple units, can bring forth rich collective dynamics which we witness and experience on a day to day basis. The observation of neuronal avalanches measured in vitro and in vivo in different cortical systems provided the first evidence of scale-free neuronal dynamics, suggesting that the observed complexity in neuronal systems could originate from the same principles which are described by the physics of second order phase transitions in classical statistical physics. The mechanism of self-organised criticality provides an explanation how such scale-invariant dynamics, which reveals itself by the observation of power-law distributed neuronal avalanches, can be observed consistently in cortical systems. The experimentally measured critical exponents are typical for a mean field self-organised branching process. These results have been reproduced by neuronal models based on self-organised criticality which, interestingly, let to the observation of mean-field exponents on different network topologies, including regular lattices, which is not expected for conventional critical systems. This raises the question about the origin of the mean field behaviour observed experimentally. This thesis provides an answer to this open question by investigating the effect of activity-dependent plasticity in combination with the neuronal refractory time in a neuronal network. Our results show that the refractory time hinders backward avalanches forcing a directed propagation of neuronal activity. Hebbian plastic adaptation then plays the role of sculpting these directed avalanche patterns into the topology of the network and slowly changes it into a branched structure where loops are marginal. The observed mean field behaviour of neuronal systems can, therefore, be considered a robust feature of spontaneous neuronal activity. Many additional neurobiological ingredients, such as inhibitory neurons, enrich the dynamics. They play a crucial role in the functioning of cortical systems. The neurotransmitter of inhibitory synapses, such as Gamma-Aminobutyric acid (GABA), reduce the membrane potential in post-synaptic neurons and lower their probability to activate, therefore, reducing the overall activity in the network. The introduction of inhibitory neurons into a self-organised critical neuronal model modifies the dynamics and one can observe that neuronal avalanches do not scale with the system size. Since experimental measurements show scaling avalanches with inhibition, we introduce the concept of dynamical synapses. Dynamical synapses are a form of short-term plasticity and allow the direct modelling of neurotransmitter at the synapses. This provides a neuronal model which features non-conserving dynamics and enables the modelling of synaptic plasticity on two time-scales. The results show that with both short-term and long-term plasticity the… Advisors/Committee Members: Herrmann, Hans J., de Arcangelis, Lucilla.

Subjects/Keywords: info:eu-repo/classification/ddc/4; info:eu-repo/classification/ddc/530; info:eu-repo/classification/ddc/570; Data processing, computer science; Physics; Life sciences

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Michiels Van Kessenich, L. (2018). Critical Neural Networks and Pattern Recognition. (Doctoral Dissertation). ETH Zürich. Retrieved from http://hdl.handle.net/20.500.11850/277641

Chicago Manual of Style (16^th Edition):

Michiels Van Kessenich, Laurens. “Critical Neural Networks and Pattern Recognition.” 2018. Doctoral Dissertation, ETH Zürich. Accessed April 13, 2021. http://hdl.handle.net/20.500.11850/277641.

MLA Handbook (7^th Edition):

Michiels Van Kessenich, Laurens. “Critical Neural Networks and Pattern Recognition.” 2018. Web. 13 Apr 2021.

Vancouver:

Michiels Van Kessenich L. Critical Neural Networks and Pattern Recognition. [Internet] [Doctoral dissertation]. ETH Zürich; 2018. [cited 2021 Apr 13]. Available from: http://hdl.handle.net/20.500.11850/277641.

Council of Science Editors:

Michiels Van Kessenich L. Critical Neural Networks and Pattern Recognition. [Doctoral Dissertation]. ETH Zürich; 2018. Available from: http://hdl.handle.net/20.500.11850/277641

ETH Zürich

8. Vetter, Roman. Packing of Elastic Wires in Three-Dimensional Cavities.

Degree: 2011, ETH Zürich

URL: http://hdl.handle.net/20.500.11850/262486

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Vetter, R. (2011). Packing of Elastic Wires in Three-Dimensional Cavities. (Thesis). ETH Zürich. Retrieved from http://hdl.handle.net/20.500.11850/262486

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Vetter, Roman. “Packing of Elastic Wires in Three-Dimensional Cavities.” 2011. Thesis, ETH Zürich. Accessed April 13, 2021. http://hdl.handle.net/20.500.11850/262486.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Vetter, Roman. “Packing of Elastic Wires in Three-Dimensional Cavities.” 2011. Web. 13 Apr 2021.

Vancouver:

Vetter R. Packing of Elastic Wires in Three-Dimensional Cavities. [Internet] [Thesis]. ETH Zürich; 2011. [cited 2021 Apr 13]. Available from: http://hdl.handle.net/20.500.11850/262486.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Vetter R. Packing of Elastic Wires in Three-Dimensional Cavities. [Thesis]. ETH Zürich; 2011. Available from: http://hdl.handle.net/20.500.11850/262486

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

ETH Zürich

9. Yoshimatsu, Ryuta. Granular Matter: Electrostatics.

Degree: 2017, ETH Zürich

URL: http://hdl.handle.net/20.500.11850/196492

Subjects/Keywords: info:eu-repo/classification/ddc/530; Physics

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Yoshimatsu, R. (2017). Granular Matter: Electrostatics. (Doctoral Dissertation). ETH Zürich. Retrieved from http://hdl.handle.net/20.500.11850/196492

Chicago Manual of Style (16^th Edition):

Yoshimatsu, Ryuta. “Granular Matter: Electrostatics.” 2017. Doctoral Dissertation, ETH Zürich. Accessed April 13, 2021. http://hdl.handle.net/20.500.11850/196492.

MLA Handbook (7^th Edition):

Yoshimatsu, Ryuta. “Granular Matter: Electrostatics.” 2017. Web. 13 Apr 2021.

Vancouver:

Yoshimatsu R. Granular Matter: Electrostatics. [Internet] [Doctoral dissertation]. ETH Zürich; 2017. [cited 2021 Apr 13]. Available from: http://hdl.handle.net/20.500.11850/196492.

Council of Science Editors:

Yoshimatsu R. Granular Matter: Electrostatics. [Doctoral Dissertation]. ETH Zürich; 2017. Available from: http://hdl.handle.net/20.500.11850/196492

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