Reaction Speed Research Articles

Experimental Research on the Performance Characteristics of Grouting Slurry in a High-Ground-Temperature Environment

Grouting materials with good thermal insulation and reinforcement properties are the key factors in solving the temperature control problems of high geothermal tunnels using curtain grouting, as the existing grouting materials are unable to take into account the working performance and thermal insulation properties of high-temperature environments. In view of the above problems, this paper configures a high geothermal tunnel red-mud-based grouting material (RMGS) using red mud, carries out tests on the working performance (viscosity, setting time, and compressive strength) and thermal insulation performance (thermal conductivity and specific heat capacity) of the grouting materials at different temperatures (20, 40, 60, and 80 °C), and analyses the variation rules and micro-mechanisms of the various properties at different temperatures. The results show that the increase in temperature will accelerate the viscosity development and condensation of the grouting material and will also lead to the acceleration of the attenuation of the thermal conductivity of the three types of grouting material and the reduction in specific heat capacity. In addition, the appropriate temperature can improve the compressive strength of the material. The increase in temperature will accelerate the hydration reaction speed of the grouting material and will also lead to the development of the internal pore space of the material, which affects the macroscopic properties of the material and is the reason for the effect of the temperature on the performance of the grouting material. In terms of application, the cement slurry is suitable for grouting in a static water environment, the cement–water glass bi-liquid slurry is suitable for grouting in a dynamic water environment, and the RMGS is suitable for grouting in a high-ground-temperature environment.

Association of subjective and objective cognitive performance to self‐rated driving ability in older adults

AbstractBackgroundOlder drivers often self‐regulate their driving behaviours to avoid more challenging situations that may lead to increased driving risk. However, other research also indicates that many older adults overestimate their driving ability, and therefore may be at risk of road traffic incidents due to not self‐regulating accurately. Understanding how self‐rated driving relates with cognitive performance can uncover markers for at‐risk driving behaviours. The present study therefore aimed to establish how self‐rated driving ability within a healthy older adult cohort relates to subjective and objective cognitive performance.Method925 cognitively healthy individuals were recruited to take part in an online cohort study (age: 71.07, % female = 55.56). Participants completed questionnaires examining driving behaviour and subjective cognitive performance. Subjective cognition was measured by a questionnaire examining spatial ability and memory performance across the lifespan and within the past 3 months. A subjective cognitive change measure was established by subtracting lifetime cognition ratings from recent cognition ratings. Participants then completed a cognitive battery in domains associated with driving performance. Hierarchical regression modelling was conducted to establish how self‐rated driving ability was associated with subjective and objective cognitive performance after controlling for age and gender effects.ResultWithin subjective cognition, individuals who rated their spatial ability and memory performance higher also rated their driving ability higher, and greater subjective cognitive change within both memory and spatial ability was predictive of lower self‐rated driving ability. Within objective cognitive performance, individuals with faster reaction speeds and faster Trail Making Test‐B completion time rated their driving abilities higher. Interestingly, when included in the same regression model, only subjective cognitive measures were predictive of self‐rated driving ability.ConclusionPrevious studies have found that self‐perceived driving ability is a more accurate indicator of self‐regulation behaviour than actual driving ability. Here, we show that subjective cognitive measures were more predictive of self‐rated driving ability than objective cognitive measures within a healthy older adult cohort. These findings add to the understanding in how cognition interacts with self‐regulation behaviour and provides an opportunity for comparison in self‐regulation driving behaviour within prodromal and clinical dementia.

Communicative Tolerance as a Psychological Phenomenon

The aim of our research is to show elements of communicative tolerance, to emphasize the actuality of this problem, to introduce communicative tolerance as a psychological phenomenon, which is especially interested in Psycholinguistics and Sociolinguistics. Methods of the research. The following theoretical methods of the research were used to solve the tasks formulated in the article: a categorical method, structural and functional methods, the methods of the analysis, systematization, modeling and generalization. The method of organizing empirical research was used as an experimental method. The results of the research. We proved that communicative tolerant speech was a means of communication in its form, it was directly related to the mental characteristics and states of the individual (as a manifestation of different feelings: moods, emotions, euphoria, anxiety, frustration, etc.; as a manifestation of the person’s attention: concentration, inattention; as a manifestation of will, determination, confusion, composure; as a manifestation of thinking: doubts, confidence; as a manifestation of imagination: dreams, creative thoughts). Conclusions. In our research we proved that speech behavior was caused by the following social factors: culture, national characteristics, ethics, education and interpersonal communication, which in the process of internalization have become internal components of mental structures. At the same time, the external manifestations of psychophysiological processes of communicative tolerance in human speech behavior are expressed from the phonetic side of speech (as vibration of the person’s voice, timbre modulation, increased tempo, speed of speech reactions).

Internal states as a source of subject-dependent movement variability are represented by large-scale brain networks

Humans’ ability to adapt and learn relies on reflecting on past performance. These experiences form latent representations called internal states that induce movement variability that improves how we interact with our environment. Our study uncovered temporal dynamics and neural substrates of two states from ten subjects implanted with intracranial depth electrodes while they performed a goal-directed motor task with physical perturbations. We identified two internal states using state-space models: one tracking past errors and the other past perturbations. These states influenced reaction times and speed errors, revealing how subjects strategize from trial history. Using local field potentials from over 100 brain regions, we found large-scale brain networks such as the dorsal attention and default mode network modulate visuospatial attention based on recent performance and environmental feedback. Notably, these networks were more prominent in higher-performing subjects, emphasizing their role in improving motor performance by regulating movement variability through internal states.

Spreading speed of an impulsive reaction–diffusion model with non-monotone birth function and age structure

In this paper, we study the spreading speed and traveling wave of an impulsive reaction–diffusion model with non-monotone birth function and age structure, which models the evolution of annually synchronized emergence of adult population with maturation. Our result is an extension to that recently established in Bai, Lou and Zhao (J. Nonlinear Sci. 2022). Numerical simulations are also performed to illustrate our result.

3D-DNA walking nanomachine based on catalytic hairpin assembly and copper nanoclusters for sensitive detection of hepatitis C virus

Rapid and accurate detection of the hepatitis C virus (HCV) is essential for early diagnosis and prevention of virus transmission. This study presents a novel approach that combines the three-dimensional (3D)-DNA walking nanomachine with catalytic hairpin assembly (CHA) and copper nanoclusters (CuNCs). By integrating CHA with the 3D DNA walking nanomachine, efficient target amplification on 3D surfaces was achieved, leading to improved reaction speed and detection performance. Terminal deoxynucleotidyl transferase (TdT) was utilized to generate T-rich DNA sequences. These sequences served as templates for the formation of CuNCs, which functioned as the readout signal. The optimized 3D-DNA walking nanomachine exhibited excellent sensitivity in detecting HCV, with a detection limit of 42.4 pM and a linear range of 100 pM to 2 nM. The biosensor demonstrated excellent selectivity and reproducibility, with a recovery rate ranging from 94% to 108% for the detection of real samples. This design holds great potential for sensitive, label-free, and reliable detection of HCV in clinical settings. Furthermore, the versatility of this approach allows for the customization of target sequences, thereby facilitating the detection of various nucleic acid targets. Therefore, this method has the potential to advance personalized medicine, disease management, and genetic analysis in the field of molecular diagnosis.

COMPARISON OF UPPER LIMB REACTION SPEED BETWEEN YOUNG TABLE TENNIS AND BADMINTON ATHLETES USING THE LYMMIC ELECTRONIC SYSTEM

<p>The aim of the present study was to compare the upper limb reaction time between young athletes (boys) of table tennis and badminton. Two groups of 14 table tennis and badminton athletes (a total of 28 athletes) with a mean age of 14±1.65 and mean involvement in these sports of 5±1.32 were the sample of the study. The visual stimulus tests used to record reaction times were as follows: a) left hand simple reaction time test, b) right hand simple reaction time test, c) left hand choice reaction time test, d) right hand choice reaction time test. The tools used for the measurements were a special light sensor and other technological means. ANOVA and Duncan’s multiple range test (p<0.05) were applied for statistical data processing. The analysis of the results showed no statistically significant differences in any of the 4 tests of the athletes. The findings and the way of measuring reaction speed could be used by the athletes’ coaches to enrich and improve the training process.</p><p> </p><p><strong> Article visualizations:</strong></p><p><img src="/-counters-/soc/0091/a.php" alt="Hit counter" /></p>

A Ketone Monoester with Carbohydrate Improves Cognitive Measures Postexercise, but Not Performance in Trained Females.

The acute ingestion of a ketone monoester with the coingestion of a carbohydrate (KME + CHO) compared with carbohydrate (CHO) was investigated on cycling performance and cognitive performance in trained females. Using a two condition, placebo-controlled, double-blinded and crossover design, 12 trained females (mean ± SD: age, 23 ± 3 yr; height, 1.64 ± 0.08 m; mass, 65.2 ± 12.7 kg) completed a baseline assessment of cognitive performance (psychomotor vigilance testing (PVT), task switching, and incongruent flanker), followed by 6 × 5-min intervals at 40%, 45%, 50%, 55%, 60%, and 65% of their maximal power output (W max ) and then a 10-km time trial, concluding with the same assessments of cognitive performance. Participants consumed either 375 mg·kg -1 body mass of KME with a 6% CHO solution (1 g·min -1 of exercise) or CHO alone, across three boluses (50:25:25). Blood β-hydroxybutyrate concentrations averaged 1.80 ± 0.07 and 0.13 ± 0.01 mM during exercise in KME + CHO and CHO, respectively. Blood glucose decreased after drink 1 of KME + CHO (~15%; P = 0.01) but not CHO, and lactate concentrations were lower in KME + CHO at 50%, 55%, 60%, and 65% W max (all P < 0.05) compared with CHO. Despite these changes, no differences were found between conditions for time trial finishing times (KME + CHO, 29.7 ± 5.7 min; CHO, 29.6 ± 5.7 min; P = 0.92). However, only KME + CHO resulted in increases in psychomotor vigilance testing speed (~4%; P = 0.01) and faster reaction times (~14%; P < 0.01), speed (~15%; P < 0.01), and correct responses (~13%; P = 0.03) in the incongruent flanker during posttesting compared with CHO. The acute ingestion of a KME + CHO elevated blood β-hydroxybutyrate and lowered glucose and lactate across multiple time points during exercise compared with CHO. Although these changes did not affect physical performance, several markers of cognitive performance were improved by the addition of a KME in trained females.

A case study of a virtual reality-based drink driving educational tool

Road traffic accidents are of major concern and could be reduced by better education. This paper describes the development of a virtual reality (VR) app that mimics the effects of alcohol on a driver. It was developed using Unity (version 2019.3.14), smartphone and Google Cardboard™. The user experiences a car following a predetermined route that is lined with trees and objects (traffic lights, road signs and other cars) which they need to spot and react to. By using graphical filters and time delays the driver has a feeling of being under the influence of alcohol. Twenty volunteers (18–60 years old; mean age ± sd 25.5 ± 11.6) participated in its evaluation. Data were collected on concentration times, reaction speed and observation of objects in both the alcohol simulated (impaired) and non-simulated (unimpaired) runs. Data were analysed using paired t-test. The result showed that people spent longer concentrating on objects in the impaired vs unimpaired run (10.72 ± 5.07 vs 5.30 ± 4.22 s n:20; p < 0.0001). The average reaction speed to objects in the unimpaired run was lower than in the impaired run (1.44 ± 0.66 vs 2.66 ± 0.28 s n:20; p < 0.001). Seventeen out of twenty subjects spotted all the required objects in the unimpaired whereas only seven out of twenty spotted all the objects in the impaired run (p < 0.001). The authors have shown that an inexpensive VR app can be used to demonstrate to users the effect that alcohol can have on concentration, reaction speeds and observational skills.

Time Variation in the News–Returns Relationship

Abstract The speed of stock price reaction to news exhibits substantial time variation. Higher risk-bearing capacity of financial intermediaries, lower passive ownership of stocks, and more informative news increase price responses to contemporaneous news; surprisingly, these interaction variables also increase price responses to lagged news (underreaction). A simple model with limited attention and three investor types (institutional, noninstitutional, and passive) predicts the observed variation in news responses. A long–short trading strategy based on news sentiment earns high returns, which increase when conditioning on the interaction variables. The interactions we document are robust to the choice of news source.

Volleyball players’ mastery of sports skills and improvement of competitive level based on big data analysis

Abstract This paper first analyzes the basic law of the formation process of volleyball skills, puts forward the four-stage theory based on this, and then gives the elements of modern volleyball players’ competitive ability. Then, the evaluation system of volleyball players’ competitive level is constructed, the weight of the index is calculated, and the data is analyzed by grey correlation analysis, entropy method and other algorithms. Finally, data mining algorithms such as least square support vector regression and long and short memory neural networks are used to mine different kinds of data to achieve the purpose of risk prediction and timely release of early warning information. Finally, the women’s volleyball team of B City is taken as an example to evaluate and test. The results show that the top four weights of the secondary indexes are running height, field of vision, serving skill score and height, and their weights are 0.5157, 0.4862, 0.4431 and 0.4248, respectively. It shows that volleyball players can improve their muscle reaction speed by actively developing the explosive power of their lower limbs so as to improve the mastery of volleyball skills and enhance the level of volleyball competition.

The development of spatial orientation in children 5-6 years old with visual impairment

Relevance. At the present stage, despite a significant amount of research and various methodological developments, the problem of the development of spatial orientation in children aged 5-6 years with visual impairment remains relevant. The age period of pre-school and junior schoolchildren is called the "golden age", referring to the rate of development of coordination abilities. To develop coordination abilities, we recommend using: multicolored cubes, gymnastic sticks, ropes, balls of different colors and sizes: small, medium (including "sound balls") and large balls. When conducting classes, we recommend using methodological techniques based on motor activity.The aim is to determine the mechanisms of spatial orientation development in children with visual impairments.Organization and methods of research. Visual impairment has a negative effect on the overall physical development of children and their health. In children with visual pathology, there is a significant lag in physical development, and the ability to assess and regulate spatiotemporal and dynamic parameters is significantly reduced.The results of the study and their discussion. The main factor in the development of orientation in the classroom is the gradual dynamic introduction of more complex exercises into classes.Conclusions. When conducting classes, it is necessary to focus on the assessment of indicators of such parameters as speed of motor reaction, orientation in space, dexterity, which are most significant in the development of orientation in space.

RSM modelling and optimization for performance evaluation of biodiesel production process from livistona jenkinsiana using NaOH as a catalyst

The production of biodiesel from conventional vegetable oils is limited by the high cost and competition with food supply. Therefore, there is a need to explore new and underutilized feedstocks that can provide abundant and low-cost oil for biodiesel production. Livistona jenkinsiana is a palm species that grows in tropical and subtropical regions of Asia. It produces oil-rich fruits that are usually discarded as waste. In this work, biodiesel was produced from Livistona jenkinsiana through transesterification reaction, and the parametric analysis was carried out. The process parameters such as reaction temperature, molar ratio, reaction time, and catalyst amount were studied, and yield (Y) was modelled using response surface methodology (RSM) as a modelling tool in MINITAB@17.1.0 software. A second-order RSM model for biodiesel yield was developed as a function of temperature, catalyst, and the molar ratio, which could predict the biodiesel yield. ANOVA results showed that temperature, catalyst, and molar ratio played an important role in the transesterification process. The optimization result showed that the optimal conditions were attained at a temperature of 61.78 °C, methanol to oil molar ratio 9.25:1, and catalyst concentration of 0.86 wt%. The highest biodiesel yield predicted was 94.47%. The reaction was carried out at a constant reaction speed of 500 rpm for 1.5 h of reaction time. The physicochemical properties of the produced biodiesel indicate that the biodiesel from Livistona jenkinsiana oil (LJO) is ideal for the production of biodiesel.

Feedback delay of sports intelligent learning system based on model predictive control and artificial intelligence

At present, in terms of model predictive control theory and model applications, two-layer segmented linear grid models are dominant. The two-layer piecewise linear lattice model is more effective, does not require too many parameters and is easy to calculate. Since the multi-layer model predictive control is based on a two-layer model, it is very important to study the mechanism and optimization methods of the two-layer model. Artificial intelligence comes from computer science. It tries to understand the nature of intelligence and create new intelligent machines that can react like human intelligence. Research in this field involves robotics, speech recognition, image recognition, natural language processing, etc. Since the emergence of artificial intelligence, theory and technology have gradually matured, and its application fields have also increased. The technological products created by artificial intelligence will embody the development of human wisdom in the future. Sports intelligence learning was first proposed by Lins. Linsley found that under laboratory conditions, by observing and recording the learner's behavior frequency and reaction speed, and adjusting the learning activities based on this, a better learning effect can be obtained. The combination of sports intelligence learning and behaviorist learning theory forms a systematic and accurate teaching method. Video system feedback delayed learning is a part of multimedia education technology. In recent years, multimedia technology has been widely used in various educational fields. By reviewing the application research of multimedia teaching technology in education, we have determined the areas related to the delay of the video system feedback, and guided the application research of the video feedback system in education.

Maximizing biodiesel yield of a non-edible chinaberry seed oil via microwave assisted transesterification process using response surface methodology and artificial neural network techniques

In this study, the non-edible Chinaberry Seed Oil (CBO) is converted into biodiesel using microwave assisted transesterification. The objective of this effort is to maximize the biodiesel yield by optimizing the operating parameters, such as catalyst concentration, methanol-oil ratio, reaction speed, and reaction time. The designed setup provides a controlled and effective approach for turning CBO into biodiesel, resulting in encouraging yields and reduced reaction times. The experimental findings reveal the optimal parameters for the highest biodiesel yield (95 %) are a catalyst concentration of 1.5 w/w, a methanol-oil ratio of 6:1 v/v, a reaction speed of 400 RPM, and a reaction period of 3 min. The interaction of the several operating parameters on biodiesel yield has been investigated using two methodologies: Response Surface Methodology (RSM) and Artificial Neural Network (ANN). RSM provides better modeling of parameter interaction, while ANN exhibits lower comparative error when predicting biodiesel yield based on the reaction parameters. The percentage improvement in prediction of biodiesel yield by ANN is found to be 12 % as compared to RSM. This study emphasizes the merits of both the approaches for biodiesel yield optimization. Furthermore, the scaling up this microwave-assisted transesterification system for industrial biodiesel production has been proposes with focus on its economic viability and environmental effects.

MOTOR CONTROL AND COGNITIVE FUNCTIONS RECOVERY DURING FORCED AWAKENING FROM SLOW-WAVE DAYTIME SLEEP

The recovery mechanisms of various forms of behavior upon awakening from sleep are still not well understood. In this work, we investigated the recovery of simple motor reactions to visual stimuli, fine hand-eye coordination, and abstract thinking upon awakening from the deepest, SWS stage of daytime sleep. Subjects were offered two types of tasks: visual-motor tasks in which it was necessary to control a moving object; and arithmetic, in which it was necessary to determine the correctness of the proposed equalities in wakefulness before sleep and during the first 2 minutes of awakening from sleep. The results obtained showed that the speed of a simple motor reaction to the appearance of a visual stimulus reached the wakefulness level almost immediately after awakening (within 4 seconds), while the restoration of the ability to determine the correctness or incorrectness of arithmetic equalities, as well as the ability to accurately control the trajectory of a moving object required much more time: about 40 seconds (in the arithmetic task) and 60 seconds (in the visual-motor task). The power of the alpha-rhythm upon awakening was higher than in wakefulness. Delta-rhythm power was increased only at the beginning of awakening while task performing was difficult, and in the second minute of awakening the delta-rhythm decreased when task performing was restored. Our data indicate that simple and complex forms of behavior upon awakening are not restored simultaneously.

Research on control strategy of flywheel energy storage system based on active disturbance rejection control

The flywheel energy storage system (FESS) has been attracting the attention of national and international academicians gradually with its benefits such as high energy power density, high conversion productivity, and inexpensive pollution. For the mutual limitation problem of reaction speed and overshoot of the conventional PI controller, it is hard to satisfy the demand of high efficiency control. In this study, the Active Disturbance Rejection Controller (ADRC) is adopted to substitute the classical PI controller in the flywheel energy storage control system. The control system of an external loop of speed and an internal loop of current is adopted at the motor side. The standard ADRC is adopted by increasing the new nonlinear control function. The control system adopted the control strategy of the DC bus voltage external loop and the current internal loop on the grid side, as well as the second-order Linear Active Disturbance Rejection Controller (LADRC), to enhance the control ability of the DC bus voltage. In the charge/discharge control of the FESS, both the velocity external loop and current internal loop control strategies are utilized to simplify the system structure. The performance shows that the improved control system could effectively enhance the charging and discharging speed of the FESS and effectively suppress the DC bus voltage rise caused by flywheel state switching so that the system has better robustness.

Interindividual variability in coherence between self-reported alertness and performance in shift workers

ObjectivesEvidence indicates that self-reported measures of alertness do not always reflect performance impairments. The present study aims to explore whether subjective and objective measures of vigilance vary in the same direction in individuals working nights. MethodsA total of 76 police officers participated to a month-long observational study. They worked either a 2 or 3-shift system during which they self-reported alertness and completed a psychomotor vigilance task several times a day. ResultsA reduction in alertness and reaction speed was observed with time awake. At the group level, changes in alertness and reaction speed with time awake were positively correlated during night shifts only. In 63.6% of the officers, changes were coherent between both variables. The other officers reported that their alertness dropped (25.5%) or improved (10.9%) whereas their performance changed in the opposite direction. ConclusionSignificant interindividual variability exists in self-appraisal vigilance impairment due to night shift work.

Exploring the Potential of Edge Computing: Use Cases and Benefits

Abstract: As cloud services and the Internet of Things continue to grow, a new computing paradigm has emerged - Edge Computing. This paper aims to explore the potential of Edge Computing by highlighting distinct use cases and benefits. By processing data at the network's edge, Edge Computing can address issues such as reaction speed, battery life, and data security. This paper also discusses the difference between cloud computing and Edge Computing, and presents a case study to demonstrate the practical applications of Edge Computing. The findings of this paper suggest that Edge Computing has the potential to revolutionize various industries and improve access quality for users.

Enhanced hydrogen generation in low-range acidic solutions using Mg2NiH4 powders and their mixtures ball-milled with NaCl and fused silica

Hydrogen production through hydrolysis shows a promise as a green and sustainable energy source that can be used for urgent need of energy on-board. This study presents a novel approach to boost the speed of hydrolysis reactions by utilizing Mg2NiH4 powder. The approach involves ball milling with NaCl and fused silica additives, that open additional active areas and accelerate the hydrolysis process. A comprehensive analysis encompasses morphology, elemental mapping, chemical bonding, structural changes, and surface area determination of the prepared powders. The hydrolysis reactions is performed using acetic acid solutions with different molarities (0.25 M, 0.12 M, and 0.06 M), as well as tap water. The impact on kinetics is profound, with reaction rates varying between 600 and 3000 ml/min during the initial seconds for different powders. Moreover, the study examines the application of such hydrolysis system for electricity generation through a proton-exchange membrane fuel cell.