386,640 research outputs found
ROBOTRAN: a powerful symbolic gnerator of multibody models
The computational efficiency of symbolic generation was at the root of the emergence of symbolic multibody programs in the eighties. At present, it remains an attractive feature of it since the exponential increase in modern computer performances naturally provides the opportunity to investigate larger systems and more sophisticated models for which real-time computation is a real asset. <br><br> Nowadays, in the context of mechatronic multibody systems, another interesting feature of the symbolic approach appears when dealing with enlarged multibody models, i.e. including electrical actuators, hydraulic devices, pneumatic suspensions, etc. and requiring specific analyses like control and optimization. Indeed, since symbolic multibody programs clearly distinguish the modeling phase from the analysis process, extracting the symbolic model, as well as some precious ingredients like analytical sensitivities, in order to export it towards any suitable environment (for control or optimization purposes) is quite straightforward. Symbolic multibody model portability is thus very attractive for the analysis of mechatronic applications. <br><br> In this context, the main features and recent developments of the ROBOTRAN software developed at the Université catholique de Louvain (Belgium) are reviewed in this paper and illustrated via three multibody applications which highlight its capabilities for dealing with very large systems and coping with multiphysics issues
Fast Diffusion GAN Model for Symbolic Music Generation Controlled by Emotions
Diffusion models have shown promising results for a wide range of generative
tasks with continuous data, such as image and audio synthesis. However, little
progress has been made on using diffusion models to generate discrete symbolic
music because this new class of generative models are not well suited for
discrete data while its iterative sampling process is computationally
expensive. In this work, we propose a diffusion model combined with a
Generative Adversarial Network, aiming to (i) alleviate one of the remaining
challenges in algorithmic music generation which is the control of generation
towards a target emotion, and (ii) mitigate the slow sampling drawback of
diffusion models applied to symbolic music generation. We first used a trained
Variational Autoencoder to obtain embeddings of a symbolic music dataset with
emotion labels and then used those to train a diffusion model. Our results
demonstrate the successful control of our diffusion model to generate symbolic
music with a desired emotion. Our model achieves several orders of magnitude
improvement in computational cost, requiring merely four time steps to denoise
while the steps required by current state-of-the-art diffusion models for
symbolic music generation is in the order of thousands
Towards Scalable Synthesis of Stochastic Control Systems
Formal control synthesis approaches over stochastic systems have received
significant attention in the past few years, in view of their ability to
provide provably correct controllers for complex logical specifications in an
automated fashion. Examples of complex specifications of interest include
properties expressed as formulae in linear temporal logic (LTL) or as automata
on infinite strings. A general methodology to synthesize controllers for such
properties resorts to symbolic abstractions of the given stochastic systems.
Symbolic models are discrete abstractions of the given concrete systems with
the property that a controller designed on the abstraction can be refined (or
implemented) into a controller on the original system. Although the recent
development of techniques for the construction of symbolic models has been
quite encouraging, the general goal of formal synthesis over stochastic control
systems is by no means solved. A fundamental issue with the existing techniques
is the known "curse of dimensionality," which is due to the need to discretize
state and input sets and that results in an exponential complexity over the
number of state and input variables in the concrete system. In this work we
propose a novel abstraction technique for incrementally stable stochastic
control systems, which does not require state-space discretization but only
input set discretization, and that can be potentially more efficient (and thus
scalable) than existing approaches. We elucidate the effectiveness of the
proposed approach by synthesizing a schedule for the coordination of two
traffic lights under some safety and fairness requirements for a road traffic
model. Further we argue that this 5-dimensional linear stochastic control
system cannot be studied with existing approaches based on state-space
discretization due to the very large number of generated discrete states.Comment: 22 pages, 3 figures. arXiv admin note: text overlap with
arXiv:1407.273
The trouble with sectarianism
This chapter attempts to situate the moral panic around sectarianism in Scotland in wider relations of social power. Sectarianism valorizes symbolic distinction and separation as prohibitions against social and ideological promiscuity and contamination between established and outsider groups (Weber, 1946). Sectarianism in this sense has been eroded by widening circles of identification in Scotland. Sectarianism today takes the form of a civilising offensive mobilised by the legitimate sources of symbolic nomination to regulate and discipline outsiders defined by a chronic maladaptation to the civilising canopy of the national habitus in Scotland
The calculative reproduction of social structures : The field of gem mining in Sri Lanka
Peer reviewedPostprin
- …