Frequency, recency, and repetition effects on same and different response times.

1973 ◽  
Vol 101 (2) ◽  
pp. 330-336 ◽  
Author(s):  
Raymond S. Nickerson
Keyword(s):  
Response Times ◽  
Repetition Effects ◽  
Different Response

scholarly journals UV-B Radiation Affects Photosynthesis-Related Processes of Two Italian Olea europaea (L.) Varieties Differently

Plants ◽  
2020 ◽  
Vol 9 (12) ◽  
pp. 1712
Author(s):  
Chiara Piccini ◽  
Giampiero Cai ◽  
Maria Celeste Dias ◽  
Marco Romi ◽  
Roberta Longo ◽  
...  
Keyword(s):  
Reactive Oxygen Species ◽  
Defense Mechanisms ◽  
Photosynthetic Efficiency ◽  
Response Times ◽  
Olive Tree ◽  
Antioxidant Response ◽  
Oxygen Species ◽  
Adaptation Mechanism ◽  
Long Period ◽  
Different Response

Given the economical importance of the olive tree it is essential to study its responses to stress agents such as excessive UV-B radiation, to understand the defense mechanisms and to identify the varieties that are able to cope with it. In the light of the analysis carried out in this study, we argue that UV-B radiation represents a dangerous source of stress for the olive tree, especially in the current increasingly changing environmental conditions. Both the varieties considered (Giarraffa and Olivastra Seggianese), although resistant to the strong treatment to which they were exposed, showed, albeit in different ways and at different times, evident effects. The two varieties have different response times and the Giarraffa variety seems better suited to prolonged UV-B stress, possible due to a more efficient and quick activation of the antioxidant response (e.g., flavonoids use to counteract reactive oxygen species) and because of its capacity to maintain the photosynthetic efficiency as well as a relatively higher content of mannitol. Moreover, pigments reduction after a long period of UV-B exposure can also be an adaptation mechanism triggered by Giarraffa to reduce energy absorption under UV-B stress. Olivastra Seggianese seems less suited to overcome UV-B stress for a long period (e.g., higher reduction of Fv/Fm) and has a higher requirement for sugars (e.g., glucose) possible to counteract stress and to restore energy.

“Same” “Different” Response Times with Multi-Attribute Stimulus Differences

1967 ◽  
Vol 24 (2) ◽  
pp. 543-554 ◽  
Author(s):  
Raymond S. Nickerson
Keyword(s):  
Response Times ◽  
Visual Stimuli ◽  
Error Rates ◽  
Different Response

S's task was to decide as quickly as possible whether two simple visual stimuli were the same or different. Stimuli varied with respect to 3 attributes: size, color, and shape. Pairs of stimuli were presented either simultaneously or in sequence. “Different” RTs varied inversely with the number of attributes with respect to which the 2 stimuli of a pair differed, d. “Same” RTs were shorter than would be expected from an extrapolation of the results with d ≥ 1 (different stimuli) to include the case of d = 0 (same stimuli). Error rates were related to d in much the same way as was RT.

scholarly journals Evidence Accumulation Modelling Reveals that Gaussian Noise Accounts for Inhibition of Return

2020 ◽  
Author(s):  
Tal Seidel Malkinson ◽  
Alexia Bourgeois ◽  
Nicolas Wattiez ◽  
Pierre Pouget ◽  
Paolo Bartolomeo
Keyword(s):  
Gaussian Noise ◽  
Inhibition Of Return ◽  
Response Times ◽  
Information Criterion ◽  
Model Parameters ◽  
Noise Parameter ◽  
Evidence Accumulation ◽  
Cortical Regions ◽  
Different Response ◽  
The Right

AbstractInhibition of return (IOR) refers to the slowing of response times (RTs) for stimuli repeated at previously inspected locations, as compared with novel ones. However, the exact processing stage(s) at which IOR occurs, and its nature across different response modalities, remain debated. We tested predictions on these issues originating from the FORTIOR model (fronto-parietal organization of response times in IOR; Seidel Malkinson & Bartolomeo, 2018), and from evidence accumulation models. We reanalysed RT data from a target-target IOR paradigm (Bourgeois et al.,2013a, 2013b) by using a LATER-like evidence accumulation model (Carpenter & Williams, 1995), to test the predictions of FORTIOR, and specifically whether IOR could occur at sensory/attentional stages of processing, or at stages of decision and action selection. We considered the following conditions: manual or saccadic response modality, before or after TMS perturbation over four cortical regions. Results showed that the Gaussian noise parameter best explained both manual and saccadic IOR, suggesting that in both response modalities IOR may result from slower accumulation of evidence for repeated locations. Additionally, across stimulated regions, TMS affected only manual RTs, lowering them equally in the conditions with repeated targets (Return) and non-repeated targets (Non-return). Accordingly, the modelling results show that TMS stimulation did not significantly alter the pattern between model parameters, with the Gaussian noise parameter remaining the parameter best explaining the Return - Non-return RT difference. Moreover, TMS over the right intra-parietal sulcus (IPS) perturbed IOR by shortening the Return RT. When directly testing this effect by modelling the TMS impact in the Return condition, the Bayesian information criterion of the Gaussian noise parameter was the smallest, but this effect did not reach significance. These results support the hypothesis that target-target IOR is a predominantly sensory/attentional phenomenon, and may be modulated by activity in fronto-parietal networks.

scholarly journals Repetition effects in action selection reflect effector- but not hemisphere-specific coding

2021 ◽  
Author(s):  
Christian Seegelke ◽  
Carolin Schonard ◽  
Tobias Heed
Keyword(s):  
Reference Frame ◽  
Response Times ◽  
Action Selection ◽  
Repetition Effects ◽  
Egocentric Reference Frame ◽  
Left Hand ◽  
Body Side ◽  
Baseline Activity ◽  
Neural Populations ◽  
Allocentric Reference Frame

Action choices are influenced by future and recent past action states. For example, when performing two actions in succession, response times (RT) to initiate the second action are reduced when the same hand is used. These findings suggest the existence of effector-specific processing for action selection. However, given that each hand is primarily controlled by the contralateral hemisphere, the RT benefit might actually reflect body side or hemisphere-specific rather than effector-specific repetition effects. Here, participants performed two consecutive movements, each with a hand or a foot, in one of two directions. Direction was specified in an egocentric reference frame (inward, outward) or in an allocentric reference frame (left, right). Successive actions were initiated faster when the same limb (e.g., left hand - left hand), but not when the other limb of the same body side (e.g., left foot - left hand) executed the second action. The same-limb advantage was evident even when the two movements involved different directions, whether specified egocentrically or allocentrically. Corroborating evidence from computational modeling lends support to the claim that repetition effects in action selection reflect persistent changes in baseline activity within neural populations that encode effector-specific action plans.

scholarly journals Geochemical characterization of components of the groundwater flow system in the basin of Mexico

2019 ◽  
Vol 98 ◽  
pp. 07022
Author(s):  
Selene Olea-Olea ◽  
Oscar Escolero ◽  
Jürgen Mahlknecht
Keyword(s):  
Groundwater Flow ◽  
Response Times ◽  
Flow System ◽  
Large Population ◽  
System Component ◽  
Main Concern ◽  
Groundwater Flow System ◽  
Basin Of Mexico ◽  
Groundwater Samples ◽  
Different Response

More than 21 million people live within the Basin of Mexico. Water is the main concern of this large population, where groundwater has been intensively exploited, leading to subsidence and fracturing of the ground. It is for this reason that it’s very important to understand the behavior of groundwater flow system components. This knowledge can help to more effectively manage water use and conserve the recharge zones. The main purpose of this study is to identify and characterize the components of groundwater flow system. Cluster analysis was used to classify 303 groundwater samples into groups. The groups show that chemical concentrations increase along the trajectories of groundwater flow. We describe these groups and identify three components in the flow system; the upper zone, the intermediate zone and the inferior zone. Different water management policies are suggested for each system component, because they have different response times to the actions taken in their use and conservation.

ENERGY TRANSFER BETWEEN LIGHT WAVES IN NONLINEAR MEDIA WITH TWO DIFFERENT RESPONSE TIMES

1999 ◽  
Vol 13 (16) ◽  
pp. 541-546
Author(s):  
C. W. A. PASCHOAL ◽  
J. C. PENAFORTE ◽  
I. GUEDES
Keyword(s):  
Response Times ◽  
Dynamical Behavior ◽  
Gain Coefficient ◽  
Wave Mixing ◽  
Probe Wave ◽  
Debye Relaxation ◽  
Light Waves ◽  
Pump And Probe ◽  
Two Wave Mixing ◽  
Different Response

In this work we extend the conventional theory of the two-wave mixing in Kerr-like media, in order to take into account two different contributions to nonlinear gain. To this end, we use a modified Debye relaxation relation to obtain the dynamical behavior of the nonlinearity and consequently, derive the expressions for pump and probe wave intensities. The two-wave mixing gain coefficient Γ1 is calculated as a function of several parameters.

scholarly journals Comparing different response time threshold setting methods to detect low effort on a large-scale assessment

2021 ◽  
Vol 9 (1) ◽  
Author(s):  
James Soland ◽  
Megan Kuhfeld ◽  
Joseph Rios
Keyword(s):  
Response Time ◽  
Test Scores ◽  
Large Scale ◽  
Response Times ◽  
The United States ◽  
Small Scale ◽  
Large Scale Assessment ◽  
Different Response ◽  
Threshold Setting ◽  
Scale Data

AbstractLow examinee effort is a major threat to valid uses of many test scores. Fortunately, several methods have been developed to detect noneffortful item responses, most of which use response times. To accurately identify noneffortful responses, one must set response time thresholds separating those responses from effortful ones. While other studies have compared the efficacy of different threshold-setting methods, they typically do so using simulated or small-scale data. When large-scale data are used in such studies, they often are not from a computer-adaptive test (CAT), use only a handful of items, or do not comprehensively examine different threshold-setting methods. In this study, we use reading test scores from over 728,923 3rd–8th-grade students in 2056 schools across the United States taking a CAT consisting of nearly 12,000 items to compare threshold-setting methods. In so doing, we help provide guidance to developers and administrators of large-scale assessments on the tradeoffs involved in using a given method to identify noneffortful responses.

scholarly journals Theoretical study of mixing in liquid clouds – Part 1: Classical concept

2015 ◽  
Vol 15 (21) ◽  
pp. 30211-30267 ◽  
Author(s):  
A. Korolev ◽  
A. Khain ◽  
M. Pinsky ◽  
J. French
Keyword(s):  
Theoretical Study ◽  
Response Times ◽  
Liquid Water Content ◽  
Convective Clouds ◽  
Droplet Concentration ◽  
Microphysical Parameters ◽  
In Situ Observations ◽  
Different Response ◽  
Analytical Expressions

Abstract. Relationships between basic microphysical parameters are studied within the framework of homogeneous and extreme inhomogeneous mixing. Analytical expressions and numerical simulations of relationships between droplet concentration, extinction coefficient, liquid water content, and mean volume droplet size, formed at the final stage of mixing are presented. The expressions are used to identify type of mixing for in-situ observations obtained in convective clouds. The analysis suggests that for the set of observations investigated here, the interaction between cloudy and entrained environments is dominated by inhomogeneous mixing. Lastly, an analysis of different response times of the cloud environment undergoing mixing is presented. Comparisons of different characteristic times suggest that within the same mixing environment depending on mixing fraction some volumes may be dominated by homogeneous mixing whereas others by inhomogeneous mixing.

scholarly journals Blade Tips - Clearance and Its Control

2013 ◽  
Vol 135 (08) ◽  
pp. 66-71
Author(s):  
Lee S. Langston
Keyword(s):  
Gas Turbine ◽  
Response Times ◽  
Operating Conditions ◽  
Tip Clearance ◽  
Thermally Induced ◽  
Turbine Efficiency ◽  
Blade Tip ◽  
Different Response ◽  
Transient Operations ◽  
Blade Tip Clearance

This article focuses on studying blade tip clearance phenomena. It is important to realize that to be freely turning, a blade (or a cantilevered stator) must have a clearance gap between its tip and the engine casing (or hub). Such clearances introduce aerodynamic losses, decreasing gas turbine efficiency. Tip leakage losses in compressors can be significant and have been reviewed by the experts. During transient operations, gas turbine blade tip clearances will change based on blade/disk centrifugal loads and the different response times of engine parts to thermally induced expansions and contractions. Designers have perfected active clearance control (ACC) systems to deal with these transient conditions. ACC uses cool or hot gas path and fan air at appropriate times during transients to control the rate of expansion or contraction of internal parts adjacent to the gas path and outer casings. The research shows that continued enhancement of blade tip clearance management systems over a range of engine operating conditions has brought and will bring about gains in gas turbine efficiency.

Pitch Control for Anticipation in the Measurement of Wind Speed for Small Wind Turbines Installed in Areas With Atypical Winds

2020 ◽  
Author(s):  
Ernesto Chavero-Navarrete ◽  
Alfredo Chavez-Luna ◽  
Juan-Carlos Jáuregui-Correa ◽  
Mario Trejo-Perea ◽  
Roberto-Valentín Carrillo-Serrano ◽  
...  
Keyword(s):  
Wind Speed ◽  
Wind Turbines ◽  
Energy Demand ◽  
Fuzzy Logic Controller ◽  
Response Times ◽  
Response Speed ◽  
Longitudinal Axis ◽  
Wind Gust ◽  
Angle Of Incidence ◽  
Different Response

Abstract The production of electricity by renewable means is necessary to meet the growing energy demand and to protect the environment. Wind energy is an alternative, however, in places with a limited wind resource only the installation of small horizontal Axis wind turbines (SHAWT) is profitable. At rotor height, in this size of turbines, the wind is usually unstable with gusts and turbulence due to obstacles in its path such as buildings and trees. To reduce the effects of wind, the angle of incidence of the blade with the wind must be adaptable to guarantee the nominal rotation speed. The pitch angle is the angle of blade rotation around the longitudinal axis is commonly regulated with a Proportional-Integral-Derivative (PID) feedback controller, which works correctly when the wind is stable, but not when the wind presents drastic changes in speed, as a faster response speed is required. To correct this problem, this article presents a PID controller with automatic adjustment of the gain values and offering different response times for which a fuzzy logic controller (FLC) is used. The membership functions of the FLC are determined from the measurement of the wind speed at a calculated distance, so it is possible to anticipate the response of the actuator to the arrival of a wind gust to the rotor. The algorithm is implemented in 14 kW SHAWT where the difference of performance versus a conventional controller is quantified.

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