792 research outputs found

    Response-related potentials during semantic priming: the effect of a speeded button response task on ERPs

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    This study examines the influence of a button response task on the event-related potential (ERP) in a semantic priming experiment. Of particular interest is the N400 component. In many semantic priming studies, subjects are asked to respond to a stimulus as fast and accurately as possible by pressing a button. Response time (RT) is recorded in parallel with an electroencephalogram (EEG) for ERP analysis. In this case, the response occurs in the time window used for ERP analysis and response-related components may overlap with stimulus-locked ones such as the N400. This has led to a recommendation against such a design, although the issue has not been explored in depth. Since studies keep being published that disregard this issue, a more detailed examination of influence of response-related potentials on the ERP is needed. Two experiments were performed in which subjects pressed one of two buttons with their dominant hand in response to word-pairs with varying association strength (AS), indicating a personal judgement of association between the two words. In the first experiment, subjects were instructed to respond as fast and accurately as possible. In the second experiment, subjects delayed their button response to enforce a one second interval between the onset of the target word and the button response. Results show that in the first experiment a P3 component and motor-related potentials (MRPs) overlap with the N400 component, which can cause a misinterpretation of the latter. In order to study the N400 component, the button response should be delayed to avoid contamination of the ERP with response-related components

    Low-energy fusion caused by an interference

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    Fusion of two deuterons of room temperature energy is studied. The nuclei are in vacuum with no connection to any external source (electric or magnetic field, illumination, surrounding matter, traps, etc.) which may accelerate them. The energy of the two nuclei is conserved and remains small during the motion through the Coulomb barrier. The penetration through this barrier, which is the main obstacle for low-energy fusion, strongly depends on a form of the incident flux on the Coulomb center at large distances from it. In contrast to the usual scattering, the incident wave is not a single plane wave but the certain superposition of plane waves of the same energy and various directions, for example, a convergent conical wave. As a result of interference, the wave function close to the Coulomb center is determined by a cusp caustic which is probed by de Broglie waves. The particle flux gets away from the cusp and moves to the Coulomb center providing a not small probability of fusion (cusp driven tunneling). Getting away from a caustic cusp also occurs in optics and acoustics

    Classical Logical versus Quantum Conceptual Thought: Examples in Economics, Decision theory and Concept Theory

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    Inspired by a quantum mechanical formalism to model concepts and their disjunctions and conjunctions, we put forward in this paper a specific hypothesis. Namely that within human thought two superposed layers can be distinguished: (i) a layer given form by an underlying classical deterministic process, incorporating essentially logical thought and its indeterministic version modeled by classical probability theory; (ii) a layer given form under influence of the totality of the surrounding conceptual landscape, where the different concepts figure as individual entities rather than (logical) combinations of others, with measurable quantities such as 'typicality', 'membership', 'representativeness', 'similarity', 'applicability', 'preference' or 'utility' carrying the influences. We call the process in this second layer 'quantum conceptual thought', which is indeterministic in essence, and contains holistic aspects, but is equally well, although very differently, organized than logical thought. A substantial part of the 'quantum conceptual thought process' can be modeled by quantum mechanical probabilistic and mathematical structures. We consider examples of three specific domains of research where the effects of the presence of quantum conceptual thought and its deviations from classical logical thought have been noticed and studied, i.e. economics, decision theory, and concept theories and which provide experimental evidence for our hypothesis.Comment: 14 page

    Inferring choice criteria with mixture IRT models: A demonstration using ad hoc and goal-derived categories

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    Whether it pertains to the foods to buy when one is on a diet, the items to take along to the beach on one’s day off or (perish the thought) the belongings to save from one’s burning house, choice is ubiquitous. We aim to determine from choices the criteria individuals use when they select objects from among a set of candidates. In order to do so we employ a mixture IRT (item-response theory) model that capitalizes on the insights that objects are chosen more often the better they meet the choice criteria and that the use of different criteria is reflected in inter-individual selection differences. The model is found to account for the inter-individual selection differences for 10 ad hoc and goal-derived categories. Its parameters can be related to selection criteria that are frequently thought of in the context of these categories. These results suggest that mixture IRT models allow one to infer from mere choice behavior the criteria individuals used to select/discard objects. Potential applications of mixture IRT models in other judgment and decision making contexts are discussed

    Relationship between extensions and intensions in categorization: A match made in heaven?

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    The present study investigated the relationship between category extension and intension for 11 different semantic categories. It is often tacitly assumed that there is a (strong) extension–intension link. However, a recent study by Hampton and Passanisi (2016) examining the patterns of stable individual differences in concepts across participants called this hypothesis into question. To conceptually replicate their findings, two studies were conducted. We employed a category judgment task to measure category extensions, whereas a property generation (in Study 1) and property judgment task (Study 2) were used to measure intensions. Using their method, that is, correlating extension and intension similarity matrices, we found nonsignificant correlations in both studies, supporting their conclusion that similarity between individuals for extensional judgments does not map onto similarity between individuals for intensional judgments. However, multilevel logistic regression analyses showed that the properties a person generated (Study 1) or endorsed (Study 2) better predicted her own category judgments compared to other people’s category judgments. This result provides evidence in favor of a link between extension and intension at the subject level. The conflicting findings, resulting from two different approaches, and their theoretical repercussions are discussed

    Norms of age of acquisition and concreteness for 30,000 Dutch words

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    Abstract not availableMarc Brysbaert, Michaël Stevens, Simon De Deyne, Wouter Voorspoels, Gert Storm

    Lift-Enhancing Tabs on Multielement Airfoils

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    The use of flat-plate tabs (similar to Gurney flaps) to enhance the lift of multielement airfoils is extended here by placing them on the pressure side and near the trailing edge of the main element rather than just on the furthest downstream wing element. The tabs studied range in height from 0.125 to 1.25% of the airfoil reference chord. In practice, such tabs would be retracted when the high-lift system is stowed. The effectiveness of the concept was demonstrated experimentally and computationally on a two-dimensional NACA 63(sub 2)-215 Mod B airfoil with a single-slotted, 30%-chord flap. Both the experiments and computations showed that the tabs significantly increase the lift at a given angle of attack and the maximum lift coefficient of the airfoil. The computational results showed that the increased lift was a result of additional turning of the flow by the tab that reduced or eliminated now separation on the flap. The best configuration tested, a 0.5%-chord tab placed 0.5% chord upstream of the trailing edge of the main element, increased the maximum lift coefficient of the airfoil by 12% and the maximum lift-to-drag ratio by 40%

    Critical Factors Of Success In Curriculum Enhancement In The Accounting Curriculum Using SAP R/3

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    Education is a well recognized aspect of an enterprise system implementation. How to educate, what to educate, when to educate, and who to educate are common questions that get raised. As an example, of particular importance in an enterprise system context is the balance between learning how to use the system itself and in understanding the integration and process concepts behind the system. As the go-live date fast approaches and budgets are running tight, firms often limit or eliminate the concepts, such as education, and focus on the keystrokes so that employees will be able to use the system. Saint Joseph's University, a liberal arts university in the Philadelphia, Pennsylvania area, recently implemented SAP R/3 within its accounting curriculum. This implementation was done in phases and at each point during the rollout, a user questionnaire was used to assess the learning skills and abilities of the students. In the early stages of this rollout, keystrokes and navigation became paramount as students learned the menu paths and reporting information available within the system. In later courses, the skills were transparent to analysis of information as students attempted to make business decisions using a case simulation. An assessment was done before and after each course, which assisted the instructors in knowing what to emphasize and when. The purpose of this paper is to outline the structure of this delivery and the lessons learned from field experience

    The Iowa Homemaker vol.4, no.9

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    Table of Contents Creamy Candles for Christmas by Beth Bailey McLean, page 3 The Home Guide by Dorothy G. Miller, page 4 Christmas Desserts by Adele Herbst, page 5 A Project in Homemaking by Elizabeth Storms Ferguson, page 6 Let’s Have a Christmas Party by Ann Leichleiter and Marvel Secor, page 6 Home Economics in New Zealand by Lillian B. Storms, page 7 The Christmas Bird by Grace Heidbreder, page 8 Helps from Our Extension Office by Viola Jammer, page 8 Who’s There and Where by Pearl Harris, page 9 Editorial, page 10 The Work of the Juvenile Court, page 11 The Eternal Question, page 1
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