7,796 research outputs found
How active perception and attractor dynamics shape perceptual categorization: A computational model
We propose a computational model of perceptual categorization that fuses elements of grounded and sensorimotor theories of cognition with dynamic models of decision-making. We assume that category information consists in anticipated patterns of agentâenvironment interactions that can be elicited through overt or covert (simulated) eye movements, object manipulation, etc. This information is firstly encoded when category information is acquired, and then re-enacted during perceptual categorization. The perceptual categorization consists in a dynamic competition between attractors that encode the sensorimotor patterns typical of each category; action prediction success counts as ââevidenceââ for a given category and contributes to falling into the corresponding attractor. The evidence accumulation process is guided by an active perception loop, and the active exploration of objects (e.g., visual exploration) aims at eliciting expected sensorimotor patterns that count as evidence for the object category. We present a computational model incorporating these elements and describing action prediction, active perception, and attractor dynamics as key elements of perceptual categorizations. We test the model in three simulated perceptual categorization tasks, and we discuss its relevance for grounded and sensorimotor theories of cognition.Peer reviewe
Ultra-trace Cu isotope ratio measurements via multi-collector ICP-mass spectrometry using Ga as internal standard : an approach applicable to micro-samples
The capabilities of Cu isotope ratio measurements are often restricted by the small volumes of sample available and/or their low Cu concentration. In this work, an analytical approach was developed for performing Cu isotopic analysis via multi-collector ICP-mass spectrometry (MC-ICP-MS) at ultra-trace level using Ga as an internal standard for mass bias correction. The minimum concentration of Cu required for accurate and precise isotope ratio measurements was established to be 20 mu g L-1 with wet plasma conditions and 5 mu g L-1 with dry plasma conditions. The use of Ga as an internal standard for mass bias correction provided several advantages compared to Ni, i.e. improved internal precision on delta Cu-65 values and lower blank levels. Ga can also be used at a 4- fold lower concentration level than Ni. However, in wet plasma conditions, the signals of (ArO2H+)-Ar-36-O-16-H-1 and (ArNO+)-Ar-40-N-15-O-16 interfered with the signals of Ga-69(+) and Ga-71(+), respectively, while in dry plasma conditions, realized by the use of a desolvation unit, Ga-69(+) suffered from spectral interference from (ArN2H+)-Ar-40-N-14-H-1. These interferences were resolved by using medium mass resolution. For validation purposes, the approach was applied to commercially available blood and serum samples. The delta Cu-65 values for the samples measured at a concentration level of 5 mu g L-1 Cu and 5 mu g L-1 Ga using dry plasma conditions were in good agreement with those obtained for isotope ratio measurements at the "standard" concentration level of 200 mu g L-1 Cu and 200 mu g L-1 Ni using wet plasma conditions. In addition, the delta Cu-65 values obtained for micro-samples of serum/blood (volume of 100 mu L) were in good agreement with the corresponding ones obtained using the "standard" volume for isotopic analysis (500 mu L)
Aiming for Cognitive Equivalence â Mental Models as a Tertium Comparationis for Translation and Empirical Semantics
This paper introduces my concept of cognitive equivalence (cf. Mandelblit, 1997), an attempt to reconcile elements of Nidaâs dynamic equivalence with recent innovations in cognitive linguistics and cognitive psychology, and building on the current focus on translatorsâ mental processes in translation studies (see e.g. Göpferich et al., 2009, Lewandowska-Tomaszczyk, 2010; Halverson, 2014). My approach shares its general impetus with Lewandowska-Tomaszczykâs concept of re-conceptualization, but is independently derived from findings in cognitive linguistics and simulation theory (see e.g. Langacker, 2008; Feldman, 2006; Barsalou, 1999; Zwaan, 2004). Against this background, I propose a model of translation processing focused on the internal simulation of reader reception and the calibration of these simulations to achieve similarity between ST and TT impact. The concept of cognitive equivalence is exemplarily tested by exploring a conceptual / lexical field (MALE BALDNESS) through the way that English, German and Japanese lexical items in this field are linked to matching visual-conceptual representations by native speaker informants. The visual data gathered via this empirical method can be used to effectively triangulate the linguistic items involved, enabling an extra-linguistic comparison across languages. Results show that there is a reassuring level of interinformant agreement within languages, but that the conceptual domain for BALDNESS is linguistically structured in systematically different ways across languages. The findings are interpreted as strengthening the call for a cognition-focused, embodied approach to translation
Hungarian GyerekestĂŒl versus Gyerekkel (âwith [the] kidâ)
The paper analyzes the various uses of the Hungarian -stUl (âtogether withâ, âalong
withâ) sociative (associative) suffix (later in the paper referred to simply as âsociativeâ), as in
the example gyerekestĂŒl. As opposed to its comitative-instrumental suffix -vAl (âwithâ), the -
stUl suffix cannot express instrumentality. The paper aims to demonstrate the difference in
use between the comitative-instrumental -vAl and the -stUl suffix in contemporary Hungarian,
and to illuminate the historical emergence of the suffix as well as its grammatical status. It is
argued on the basis of Antal (1960) and Kiefer (2003) that -stUl cannot be analyzed as an
inflectional case suffix (such as the -vAl suffix, or -ed, -ing, or the plural in English), but
should rather be categorized as a derivational suffix (such as English dis-, re-, in-, -ance, -
able, -ish, -like, etc.). The paper also tries to shed light on the hypothetical cognitive
psychological distinction between the comitative and the sociative. It is suggested that the
sociative is based on the amalgam image schema which is derived from the LINK schema of
the comitative. The ironical reading of the sociative is an implicature in the sense of Grice
(1989) and Sperber and Wilson (1987). Psycholinguistic experimentation is proposed to
follow up on the mental representation of the sociative
Perception Based Gait Generation for Quadrupedal Characters
With the rapid expansion of the range of digital characters involved in film and game production, creating a wide variety of expressive characters has become a problem that cannot be solved efficiently through current animation methods. Key-frame animation is time-consuming and requires animation expertise. Motion capture is constrained by equipment and environment requirements and is most applicable to humanoid characters. Simulation can produce physically correct motion but does not account for expressiveness. This thesis focuses on developing a more efficient animation system using a procedural approach in which the skeletal structure and characteristics of motion that communicate weight and age in quadrupeds have been isolated and engineered as user-controlled tools and modifiers to build creature shape and synthesize cyclic gait animation. This new approach accomplished the goal of quick generation of expressive characters. It is also successful in achieving real-time animation playback and adjustment
A Multi-disciplinary Approach to the Investigation of Aspects of Serial Order in Cognition
Serial order processing or Sequence processing underlies many human activities such as speech, language, skill learning, planning, problem solving, etc. Investigating the\ud
neural bases of sequence processing enables us to understand serial order in cognition and helps us building intelligent devices. In the current paper, various\ud
cognitive issues related to sequence processing will be discussed with examples. Some of the issues are: distributed versus local representation, pre-wired versus\ud
adaptive origins of representation, implicit versus explicit learning, fixed/flat versus hierarchical organization, timing aspects, order information embedded in sequences, primacy versus recency in list learning and aspects of sequence perception such as recognition, recall and generation. Experimental results that give evidence for the involvement of various brain areas will be described. Finally, theoretical frameworks based on Markov models and Reinforcement Learning paradigm will be presented. These theoretical ideas are useful for studying sequential phenomena in a principled way
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'Democracy begins in conversationâ: the phenomenology of problem-based learning and legal education
Learning is complex for any number of reasons. One of these is that it doesnât take
place in a laboratory: it happens in real places, within and between real people, and
as a consequence it takes place in multi-factorial environments. At every stage of
learning in Higher Education (HE), from student choice of institution and programme,
to the transfer of learning from theory to practice, to a single institutionâs
or a teacherâs evaluation of teaching and learning, there are many causal factors that
affect educational process and outcome. The complexities and variables created by the
interaction of such multiple factors, well known in the field of education, make learning
a highly complex phenomenon to analyse and understand
Real-time rendering and simulation of trees and snow
Tree models created by an industry used package are exported and the structure extracted in order to procedurally regenerate the geometric mesh, addressing the limitations of the application's standard output. The structure, once extracted, is used to fully generate a high quality skeleton for the tree, individually representing each
section in every branch to give the greatest achievable level of freedom of deformation and animation. Around the generated skeleton, a new geometric mesh is wrapped
using a single, continuous surface resulting in the removal of intersection based render artefacts. Surface smoothing and enhanced detail is added to the model dynamically
using the GPU enhanced tessellation engine.
A real-time snow accumulation system is developed to generate snow cover on a dynamic, animated scene. Occlusion techniques are used to project snow accumulating faces and map exposed areas to applied accumulation maps in the form of dynamic textures. Accumulation maps are xed to applied surfaces, allowing moving objects to maintain accumulated snow cover. Mesh generation is performed dynamically during the rendering pass using surface oïżœsetting and tessellation to enhance
required detail
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