scholarly journals The anticipatory and reaction time behaviors of the futsal goalkeeper

2020 ◽  
Vol 32 (1) ◽  
Author(s):  
Silvia Leticia Da Silva ◽  
Estefan Gemas Neto ◽  
Gisele Carla Dos Santos Palma ◽  
Antonio Sabino Silva Filho ◽  
Umberto Cesar Corrêa
Keyword(s):  
Reaction Time ◽  
Time Criterion ◽  
The Moment

This study aimed to investigate the goalkeeper’s anticipatory and reaction time behaviors. For this purpose, 50 kicks performed by male futsal players were analyzed. The time of goalkeeper’s response to a kick was analyzed in relation to the kick outcome, court zone and distance between the goalkeeper and player who performed the kick. The goalkeeper’s anticipation and reaction time behaviors were those below and above 200 ms as the time criterion, respectively, by considering the moment the player began the preparation for kicking to the moment the goalkeeper began to respond to it.  Results showed that the goalkeeper performed anticipatory behaviors predominantly when (i) goals were attained and (ii) kicks were performed in the center and attack court’s zones (iii) at a distance ranging from 5.97 to 7.84 meters. In these conditions, the goalkeepers’ anticipatory behaviors implied ineffective performances.

scholarly journals Reaction to a Visual Stimulus: Anticipation with Steady and Dynamic Contractions

2019 ◽  
Vol 69 (1) ◽  
pp. 17-27
Author(s):  
Agostina Casamento-Moran ◽  
Stefan Delmas ◽  
Seoung Hoon Park ◽  
Basma Yacoubi ◽  
Evangelos A. Christou
Keyword(s):  
Reaction Time ◽  
Planning Process ◽  
Dynamic Condition ◽  
Motor Planning ◽  
Reaction Time Task ◽  
Emg Activity ◽  
Time Interval ◽  
Variable Direction ◽  
The Moment ◽  
Study Participants

Abstract Reacting fast to visual stimuli is important for many activities of daily living and sports. It remains unknown whether the strategy used during the anticipatory period influences the speed of the reaction. The purpose of this study was to determine if reaction time (RT) differs following a steady and a dynamic anticipatory strategy. Twenty‐two young adults (21.0 ± 2.2 yrs, 13 women) participated in this study. Participants performed 15 trials of a reaction time task with ankle dorsiflexion using a steady (steady force at 15% MVC) and a dynamic (oscillating force from 10‐20% MVC) anticipatory strategy. We recorded primary agonist muscle (tibialis anterior; TA) electromyographic (EMG) activity. We quantified RT as the time interval from the onset of the stimulus to the onset of force. We found that a dynamic anticipatory strategy, compared to the steady anticipatory strategy, resulted in a longer RT (p = 0.04). We classified trials of the dynamic condition based on the level and direction of anticipatory force at the moment of the response. We found that RT was longer during the middle descending relative to the middle ascending and the steady conditions (p < 0.01). All together, these results suggest that RT is longer when preceded by a dynamic anticipatory strategy. Specifically, the longer RT is a consequence of the variable direction of force at which the response can occur, which challenges the motor planning process.

scholarly journals PRACTICAL ASPECTS OF THE USE OF ANTISIPATIVE MANAGEMENT IN THE PROCESS OF ENSURING THE ECONOMIC SECURITY OF AN ENTERPRISE

2021 ◽  
Vol 22 (1) ◽  
pp. 202-210
Author(s):  
Andriy Shtangret ◽  
Elzara Topalova ◽  
Oleg Polovcev ◽  
Olena Chornenka ◽  
Andriy Musiyovskyi
Keyword(s):  
Reaction Time ◽  
Crisis Management ◽  
Early Identification ◽  
External Environment ◽  
Economic Security ◽  
Economic Opportunity ◽  
Timely Manner ◽  
Weak Signals ◽  
Sufficient Degree ◽  
The Moment

Operating in an unstable market economy environment, enterprises can achieve success in business, provided that a system of economic security is created, focused on predicting possible changes in the internal and external environment using measures. As the speed of changes in the external environment increases, it becomes more and more difficult to predict with a sufficient degree of accuracy the nature of changes, which would allow security actors to respond to them in a timely manner and with the most rational use of available resources. Early identification of a possible change in the level of economic security of an enterprise increases the reaction time to it. However, with the increase in the frequency of possible sudden changes, the degree of their predictability decreases. This means that until the moment of obtaining information sufficient for thoughtful measures, there is a shortage of time for their implementation, which can lead to the realisation of a certain threat in the form of losses or lead to the loss of a profitable economic opportunity. The main purpose of the article is to consider the essence of weak signals, to characterise the process of identifying weak signals, to formulate methodological foundations for the use of antisipative management, to determine the differences between antisipative management and adaptive and anti-crisis management in relation to the process of ensuring the economic security of an enterprise.

Olfactory Facilitation of Takeover Performance in Highly Automated Driving

2020 ◽  
pp. 001872081989313 ◽  
Author(s):  
Qiuyang Tang ◽  
Gang Guo ◽  
Zijian Zhang ◽  
Bingbing Zhang ◽  
Yingzhang Wu
Keyword(s):  
Reaction Time ◽  
Positive Impact ◽  
Auditory Modality ◽  
Automated Driving ◽  
Subsequent Performance ◽  
Within Subjects ◽  
The Moment ◽  
The Impact ◽  
Positive Effect ◽  
Light Sleep

Objective This study aims to quantify the impact of olfactory stimulation and takeover modality on the performance of takeovers in conditionally automated driving. Background Takeover requests are important for the safety of automated vehicles. The reaction time and subsequent performance of drivers in the takeover process are crucial for safety. In this study, peppermint was adopted as an auxiliary modality to the tactile and auditory design of takeover requests. Methods Sixty participants took part in the experiment, which required participants to avoid a stalled vehicle after they were awoken from a state of light sleep by a takeover request. Takeover modality (tactile, auditory, and combined) was the within-subjects factor. In the between-subjects design, half of the participants received a peppermint odor stimulation when the takeover request occurred, and the other half received a placebo (air). Results The presence of peppermint odor did not influence the reaction time, but participants did show signs of being more alert afterwards. For the moment of takeover, use of the auditory modality had a significant positive effect on reaction time compared to the tactile conditions. Conclusion Peppermint odor had a positive impact on drivers’ takeover quality when engaged in nondriving-related activities such as light sleep, and the takeover request modalities were shown to be crucial for a safe and successful takeover. Application The results will be useful as a reference for developers of automated driving systems to design human–machine interfaces, shorten the driver’s reaction time, and improve takeover quality.

scholarly journals ANALYSIS OF TRAINING METHOD OF TAEKWONDO ATHLETES WITH REACTION BALL

2022 ◽  
Vol 28 (1) ◽  
pp. 14-16
Author(s):  
Wei Zong
Keyword(s):  
Standard Deviation ◽  
Reaction Time ◽  
Standard Error ◽  
Average Score ◽  
Training Methods ◽  
Research Subjects ◽  
Level Of Evidence ◽  
Camera System ◽  
The Moment ◽  
Reaction Speed

ABSTRACT Introduction: Brief introduction: Taekwondo is a sport that integrates explosive power and reaction speed. The reaction speed of the athletes has a direct bearing on the result of the competition. Objective: To improve the reaction time effect of athletes. Methods: Forty-one Taekwondo team athletes were selected as the research subjects. Then, the training methods were introduced, and special technology using an emg tester and a synchronous camera system was implemented to analyze the earliest emg signals and the moment of the hit, the time from signal emergence to the emg reaction for reaction time, and from signal emergence to hit for the total time. Results: The average score of the 41 athletes before the test was 0.282673,with standard deviation of 0.0377349 and standard error of 0.0058932. The average score, standard deviation, and standard error of the 41 athletes after small training were 0.28217, 0.037744 and 0.005895. Conclusions: From the test results of the three training modes, the small training mode had a significant impact on the reaction time of Taekwondo athletes, while the medium and large training modes did not have significant effects. The results show that a small amount of training is best and plays a significant role in improving the reaction of an athlete. Level of evidence II; Therapeutic studies - investigation of treatment results.

The Time Course of Preparation after a First Peak: Some Constraints of Reacting Mechanisms

1974 ◽  
Vol 26 (4) ◽  
pp. 622-632 ◽  
Author(s):  
Jesus Alegria
Keyword(s):  
Reaction Time ◽  
Time Course ◽  
Reaction Times ◽  
Choice Stimulus ◽  
Starting Point ◽  
The Moment

The aim of this work was to study the time-course of preparation when a two choice stimulus arrives, in a predictable (Experiment I) or unpredictable (Experiment II) manner, after the moment at which it was expected. Subjects watched the screen of an oscilloscope on which a spot moved horizontaly. Vertical lines marked (a) the starting point of the spot's course, t0, and (b) the points in time, t1 … t1, at which the stimulus could arrive. In Experiment I five intervals between t1 and t1, ranging from 150 to 900 ms were used in different blocks of trials. In Experiment II three t1-t1 intervals, ranging from 100 to 400 ms mixed in a random way were used. In both cases subjects were asked to react as fast as possible when the stimulus was presented at moment t1. The time course of preparation was studied when the stimulus arrived at moment(s) t1. The results show that reaction time reaches a maximum 250 ms after t1, irrespectively the predictability of the t1-t1 interval. It is also shown that an interval of about 1 s was necessary to obtain reaction times as rapid as those observed at moment t1. The results are discussed in terms of the evolution of an hypothetical “state of preparation” after a maximum which remains unused.

scholarly journals MODELING THE DRIVER'S REACTION TIME TAKING INTO ACCOUNT THE INFLUENCE OF CONFLICT SITUATIONS ON CITY STREETS

2021 ◽  
Vol 4 (164) ◽  
pp. 246-251
Author(s):  
O. Prasolenko ◽  
V. Chumachenko ◽  
O. Grekova
Keyword(s):  
Reaction Time ◽  
Functional State ◽  
Mutual Influence ◽  
Movement Time ◽  
Experimental Studies ◽  
The State ◽  
Stress Index ◽  
Steering Wheel ◽  
Conflict Situations ◽  
The Moment

The driver's reaction time is the most important characteristic when driving. The driver's reaction time is the period of time from the moment the stimulus appears in the driver's field of vision until the start of the action (application of the brake pedal, accelerator, steering wheel). The response time to stimuli depends on: the driver's age; the state of his health; mental state; alcohol or drug consumption; if at the moment he is in the vehicle alone or with a passenger, etc. The functional state of the driver is a complex of characteristics of the functions and qualities of the operator, which directly or indirectly characterizes the performance of labor activity. This definition draws a line between the state of a person and the state of his individual physiological and psychophysiological functions. One of these indicators is the stress index. Heart rate is a stable and accurate indicator of functional status. The experiment involved drivers with 10-16 years of experience. The driver's cardiogram was recorded using a portable Holter and analyzed in the CardioSens CS system. According to the degree of danger, conflict situations are divided into three types: light, medium and critical. The degree of danger of a conflict situation is determined by the appearance of critical accelerations. A racelogic device was used to register the acceleration parameters. The obtained dependences of the change in the functional state of the driver and the reaction time in accordance with the number of conflict situations while driving indicate significant fluctuations in these indicators. Change in reaction time from 0.7 sec. up to 1.5 sec. associated with significant psychophysio-logical stress on the driver, the number of conflict situations of various types: the appearance of a pedestrian, dangerous maneuvering of other vehicles, etc. At the same time, the driver's stress may increase by more than 2.5 times. The article discusses an approach to modeling the driver's reaction time, taking into account the influence of conflict situations on city streets. Experimental studies of the regularities of changes in the reaction time, the stress index of drivers in traffic on city streets have been carried out. Two factor models have been built, taking into account the mutual influence of factors of movement time in urban conditions and the number of conflict situations.

Influence of an Intertrial Interval on Sequential Effects Related to Preparatory Period Duration for Reaction Time-Task

1979 ◽  
Vol 49 (3) ◽  
pp. 979-987 ◽  
Author(s):  
M. Granjon ◽  
C. A. Possamaï ◽  
G. Reynard ◽  
D. Oberti
Keyword(s):  
Reaction Time ◽  
Time Course ◽  
Memory Search ◽  
Reaction Time Task ◽  
Rest Interval ◽  
Sequential Effects ◽  
Preparatory Period ◽  
The Moment ◽  
The Cost ◽  
Relationship Of

In reaction time tasks, where the moment of occurrence of the response signal is uncertain, the temporal constraints of preparatory processes imply that subjects distribute their preparation during the preparatory period. The notion of cost of preparation has been proposed to explain the time course of these processes. This experiment was run to determine the effect of the cost of preparation on a serial-RT task and on a RT task where a rest interval of various possible durations (3, 6, or 9 sec.) is introduced. 12 subjects were tested. Data show that the amount spent on preparation during a trial affects the subject's performance during the next trials. But an hypothesis about memory search must also be advanced to explain the effect of the rest interval on the relationship of RT and the current preparatory period.

A Clock Paradigm to Study the Relationship between Expectancy and Response Force

1993 ◽  
Vol 77 (1) ◽  
pp. 163-174 ◽  
Author(s):  
Piotr Jaskowski ◽  
Rolf Verleger
Keyword(s):  
Reaction Time ◽  
Stimulus Intensity ◽  
Response Force ◽  
Warning Stimulus ◽  
The Moment ◽  
The Relationship

It has recently been demonstrated that the force used by subjects to press a response key depends on stimulation conditions such as stimulus intensity, foreperiod, etc. We performed an experiment in which response force and reaction time were measured as a function of expectancy. In contrast to the paradigms used so far, we manipulated expectancy without using warning stimuli by applying a so-called “clock-paradigm.” It enabled us to avoid the possible arousing effect of the warning stimulus. Both reaction time and response force depended on expectancy. The results suggest that response force was not affected by arousal or activation but was affected by preparatory state at the moment of making a response.

The High Resolution Scanning Transmission Electron Microscope

1974 ◽  
Vol 32 ◽  
pp. 316-317
Author(s):  
A. V. Crewe
Keyword(s):  
Electron Microscope ◽  
High Resolution ◽  
High Vacuum ◽  
Scanning Transmission Electron Microscope ◽  
Ultra High Vacuum ◽  
Resolving Power ◽  
Imaging Characteristics ◽  
Transmission Electron ◽  
Scanning Transmission ◽  
The Moment

The high resolution STEM is now a fact of life. I think that we have, in the last few years, demonstrated that this instrument is capable of the same resolving power as a CEM but is sufficiently different in its imaging characteristics to offer some real advantages.It seems possible to prove in a quite general way that only a field emission source can give adequate intensity for the highest resolution^ and at the moment this means operating at ultra high vacuum levels. Our experience, however, is that neither the source nor the vacuum are difficult to manage and indeed are simpler than many other systems and substantially trouble-free.

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