Search results for "Machine"
showing 10 items of 2592 documents
Looking for representative fit models for apparel sizing
2014
This paper is concerned with the generation of optimal fit models for use in apparel design. Representative fit models or prototypes are important for defining a meaningful sizing system. However, there is no agreement among apparel manufacturers and each one has their own prototypes and size charts i.e. there is a lack of standard sizes in garments from different apparel manufacturers. We propose two algorithms based on a new hierarchical partitioning around medoids clustering method originally developed for gene expression data. We are concerned with a different application; therefore, the dissimilarity between the objects has to be different and must be designed to deal with anthropometr…
On the Intrinsic Complexity of Learning
1995
AbstractA new view of learning is presented. The basis of this view is a natural notion of reduction. We prove completeness and relative difficulty results. An infinite hierarchy of intrinsically more and more difficult to learn concepts is presented. Our results indicate that the complexity notion captured by our new notion of reduction differs dramatically from the traditional studies of the complexity of the algorithms performing learning tasks.
The dyon charge in noncommutative gauge theories
2007
We present an explicit classical dyon solution for the noncommutative version of the Yang-Mills-Higgs model (in the Prasad-Sommerfield limit) with a tehta term. We show that the relation between classical electric and magnetic charges also holds in noncommutative space. Extending the Noether approach to the case of a noncommutative gauge theory, we analyze the effect of CP violation at the quantum level, induced both by the theta term and by noncommutativity and we prove that the Witten effect formula for the dyon charge remains the same as in ordinary space.
Mahler Measuring the Genetic Code of Amoebae
2023
Amoebae from tropical geometry and the Mahler measure from number theory play important roles in quiver gauge theories and dimer models. Their dependencies on the coefficients of the Newton polynomial closely resemble each other, and they are connected via the Ronkin function. Genetic symbolic regression methods are employed to extract the numerical relationships between the 2d and 3d amoebae components and the Mahler measure. We find that the volume of the bounded complement of a d-dimensional amoeba is related to the gas phase contribution to the Mahler measure by a degree-d polynomial, with d = 2 and 3. These methods are then further extended to numerical analyses of the non-reflexive Ma…
Machine learning for energy cost modelling in wastewater treatment plants.
2018
Understanding the energy cost structure of wastewater treatment plants is a relevant topic for plant managers due to the high energy costs and significant saving potentials. Currently, energy cost models are generally generated using logarithmic, exponential or linear functions that could produce not accurate results when the relationship between variables is highly complex and non-linear. In order to overcome this issue, this paper proposes a new methodology based on machine-learning algorithms that perform better with complex datasets. In this paper, machine learning was used to generate high-performing energy cost models for wastewater treatment plants, using a database of 317 wastewater…
Classifying Major Explosions and Paroxysms at Stromboli Volcano (Italy) from Space
2021
Stromboli volcano has a persistent activity that is almost exclusively explosive. Predominated by low intensity events, this activity is occasionally interspersed with more powerful episodes, known as major explosions and paroxysms, which represent the main hazards for the inhabitants of the island. Here, we propose a machine learning approach to distinguish between paroxysms and major explosions by using satellite-derived measurements. We investigated the high energy explosive events occurring in the period January 2018–April 2021. Three distinguishing features are taken into account, namely (i) the temporal variations of surface temperature over the summit area, (ii) the magnitude of the …
High-Speed Machines: Typologies, Standards, and Operation under PWM Supply
2018
This paper presents an overview of the most recent state of the art in the field of high-speed electric machines fed through high-frequency converters. This type of systems is rapidly wide spreading in aeronautical and automotive applications, as well as microturbines. Each typology has its own advantages and downsides, which are analytically presented in this paper. Some types of high-speed electric machines require high-frequency voltage supply, highly stressing the dielectric materials of the winding insulation system. For this reason, in high-speed electric drives, premature failure may occur and a reduction of the total system reliability has been observed in the past years. Such issue…
Estimating the Number of Changepoints in Segmented Regression Models: Comparative Study and Application
2020
This paper deals with the problem of selecting the number of changepoints in segmented regression models. The aim is to review selection criteria, namely information criteria and hypothesis testing, and to propose a novel application in the context of students' careers in higher education. The performance of the selection criteria is assessed through simulation studies. Furthermore, we investigate the relationship between University students' performance and one of its main determinants, finding out that this relationship is actually broken-line.
Obsolescence and intervention: on synthetic-biological entities.
2014
Oftentimes, topics that might fall outside of science’s remit seem to end up becoming a part of it, sooner or later. This appears to be the case of synthetic biology, a new biological science (although some maintain that it is a form of engineering, or treat it as such; Endy, 2005), which seems to have become essential to the understanding of living beings and their extreme manipulation. I believe it to be a new form of biology. In truth, synthetic biology has a long history and, conceptually speaking, may well have formed part of the interests and research efforts of our illustrious predecessors throughout the first half of the twentieth century and even earlier. In any event, and broadly …
Le genre des bris de machines : violence et mécanisation à l’aube de l’ère industrielle (Angleterre-France, 1750-1850)
2013
Les bris de machines constituent un type de violence recurrent en Angleterre et en France au debut de l’ere industrielle. Ce type de violence contestataire a ete peint essentiellement sous les traits d’une pratique masculine, impliquant le triomphe d’une conception virile des rapports sociaux et des conflits du travail. Loin d’etre marginales ou invisibles, les femmes sont pourtant bien presentes dans ces conflits, a la fois comme auxiliaires des hommes mais aussi comme actrices de plein droit insurgees contre les machines qui portent atteinte a la production domestique et a leur mode de vie. En examinant le genre des bris de machines, il s’agit a la fois de suivre comment les machines requ…