Search results for "Machine"
showing 10 items of 2592 documents
Testing for non-linearity in an artificial financial market: a recurrence quantification approach
2004
Abstract In this paper, earlier work on testing for non-linear dynamics on realizations from an artificial financial market is extended in two ways. On the one hand, Hinich’s bispectral test and White’s neural network test are computed. On the other hand, a recently developed methodology to test for hidden structures in data, inherited from Physics, is successfully applied on the realizations of the artificial market. Results among alternative tests are compared.
Boosting organizational learning through team-based talent management: what is the evidence from large Spanish firms?
2013
Talent management (TM) can crucially help optimize organizational learning (OL) processes. The aim of this article is to study whether certain TM practices related to teamwork design and dynamics stimulate and develop learning (i.e. knowledge creation) processes within the organization and across the different ontological levels (individual, group and organizational–institutional). A model linking team-based TM and OL is tested in a sample of large Spanish companies. Our empirical results emphasize the distinction between individual–group and institutional levels of learning as the two pillars of OL. The results also highlight the role of team autonomy and creativity as crucial factors for …
Using Cellular Automata for feature construction - preliminary study
2007
When first faced with a learning task, it is often not clear what a good representation of the training data should look like. We are often forced to create some set of features that appear plausible, without any strong confidence that they will yield superior learning. Beside, we often do not have any prior knowledge of what learning method is the best to apply, and thus often try multiple methods in an attempt to find the one that performs best. This paper describes a new method and its preliminary study for constructing features based on cellular automata (CA). Our approach uses self-organisation ability of cellular automata by constructing features being most efficient for making predic…
Target Classification by mmWave FMCW Radars Using Machine Learning on Range-Angle Images
2021
In this paper, we present a novel multiclass-target classification method for mmWave frequency modulated continuous wave (FMCW) radar operating in the frequency range of 77 - 81 GHz, based on custom range-angle heatmaps and machine learning tools. The elevation field of view (FoV) is increased by orienting the Radar antennas in elevation. In this orientation, the radar focuses the beam in elevation to improve the elevation FoV. The azimuth FoV is improved by mechanically rotating the Radar horizontally, which has antenna elements oriented in the elevation direction. The data from the Radar measurements obtained by mechanical rotation of the Radar in Azimuth are used to generate a range-angl…
Experimental strength of restorations with fibre posts at different stages, with and without using a simulated ligament
2011
The aim of this study was to analyse the strength and failure mode of teeth restored with fibre posts under retention and flexural-compressive loads at different stages of the restoration and to analyse whether including a simulated ligament in the experimental setup has any effect on the strength or the failure mode. Thirty human maxillary central incisors were distributed in three different groups to be restored with simulation of different restoration stages (1: only post, 2: post and core, 3: post-core and crown), using Rebilda fibre posts. The specimens were inserted in resin blocks and loaded by means of a universal testing machine until failure under tension (stage 1) and 50o flexion…
The effect of orthodontic bracket pad shape on shear bond strength, an in vitro study on human enamel
2018
Background To evaluate the effect of bracket pad shape on shear bond strength (SBS) of orthodontic brackets bonded to human enamel. Material and Methods One hundred and five extracted human maxillary permanent molars were divided into 7 groups of 15 specimens per group (n=15). Each group of teeth was bonded with 6 different shaped WildSmiles® brackets (Star, Heart, Soccer ball, Football, Flower, and Diamond) and GAC® rectangle shaped brackets. Shear debonding force was measured with an Instron universal testing machine using a knife-edged chisel 24 hours after initial bonding. Descriptive statistics (mean, standard deviation, and range) for each bracket pad shape was calculated. Analysis of…
Photoelastic analysis of conventional and locking system for treatment of mandibular angle fractures with a single plate
2021
Made available in DSpace on 2021-06-25T10:28:10Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-04-01 Background: This photoelastic analysis evaluated stress distribution in different osteosynthesis systems, conventional and locking, used for treatment of mandibular angle fractures with a single plate. Material and Methods: Angle fractures were simulated in mandibles made of photoelastic resin. Following Champy’s method, plate osteosynthesis was performed. The samples were divided into five groups: Group 1, non-fractured mandible; Group 2, two screws were installed in each segment using a conventional system; Group 3, two screws were installed in each segment using a locking system; …
Comparison of torque expression in esthetic brackets
2019
Background The objective of this work is to test the null hypothesis that there is no difference in the torque expression among different esthetic brackets. Material and methods Five ceramic self-ligating brackets (In-Ovation C - GAC, Damon Clear-Ormco, QuicKlear-Forestadent, Click-It -TP Orthodontics, Clarity SL-3M Unitek) and 4 ceramic conventional brackets (Inspire Ice-Ormco, InVu Ceramic-TP Orthodontics, Ceramic Roth-Morelli, Clarity Metal-Reinforced Ceramic Bracket-3M Unitek) were selected. Metallic Damon MX self-ligating bracket (Ormco) was used as control. Third-order moments were measured at 12o, 24o and 36o using an archwire torsion device associated with a Universal Testing Machin…
The effect of dental chair light exposure duration on shear bond strength of orthodontic brackets : an in vitro study
2018
Background The purpose of this study is to determine if the duration of exposure to the halogen overhead dental chair light has an effect on shear bond strength (SBS) of metal orthodontic brackets. Material and Methods One hundred twenty extracted human lower incisor teeth were divided into six groups (n=20/group). Each group was assigned a predetermined duration of exposure to the halogen dental chair light, set at a fixed distance, before being cured. Light exposure times of 0 minutes (Group 1-Control), 1 minute (Group 2), 2.5 minutes (Group 3), 5 minutes (Group 4), 10 minutes (Group 5), and 15 minutes (Group 6) were tested. Each tooth was subjected to an exclusion criteria examination, s…
Manipulating the alpha level cannot cure significance testing
2018
We argue that making accept/reject decisions on scientific hypotheses, including a recent call for changing the canonical alpha level from p = 0.05 to p = 0.005, is deleterious for the finding of new discoveries and the progress of science. Given that blanket and variable alpha levels both are problematic, it is sensible to dispense with significance testing altogether. There are alternatives that address study design and sample size much more directly than significance testing does; but none of the statistical tools should be taken as the new magic method giving clear-cut mechanical answers. Inference should not be based on single studies at all, but on cumulative evidence from multiple in…