Interactive effects of preparatory intervals, stimulus intensity, and experimental design on reaction time.

1969 ◽  
Vol 80 (2, Pt.1) ◽  
pp. 311-316 ◽  
Author(s):  
George Kellas ◽  
Alfred A. Baumeister ◽  
Stephen J. Wilcox
Keyword(s):  
Reaction Time ◽  
Experimental Design ◽  
Stimulus Intensity ◽  
Interactive Effects

scholarly journals Self-generation and sound intensity interactively modulate perceptual bias, but not perceptual sensitivity

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Nadia Paraskevoudi ◽  
Iria SanMiguel
Keyword(s):  
Stimulus Intensity ◽  
Empirical Support ◽  
Sound Intensity ◽  
Perceptual Bias ◽  
Perceptual Processing ◽  
Interactive Effects ◽  
Just Noticeable Difference ◽  
External Sources ◽  
Motor Actions ◽  
Near Threshold

AbstractThe ability to distinguish self-generated stimuli from those caused by external sources is critical for all behaving organisms. Although many studies point to a sensory attenuation of self-generated stimuli, recent evidence suggests that motor actions can result in either attenuated or enhanced perceptual processing depending on the environmental context (i.e., stimulus intensity). The present study employed 2-AFC sound detection and loudness discrimination tasks to test whether sound source (self- or externally-generated) and stimulus intensity (supra- or near-threshold) interactively modulate detection ability and loudness perception. Self-generation did not affect detection and discrimination sensitivity (i.e., detection thresholds and Just Noticeable Difference, respectively). However, in the discrimination task, we observed a significant interaction between self-generation and intensity on perceptual bias (i.e. Point of Subjective Equality). Supra-threshold self-generated sounds were perceived softer than externally-generated ones, while at near-threshold intensities self-generated sounds were perceived louder than externally-generated ones. Our findings provide empirical support to recent theories on how predictions and signal intensity modulate perceptual processing, pointing to interactive effects of intensity and self-generation that seem to be driven by a biased estimate of perceived loudness, rather by changes in detection and discrimination sensitivity.

scholarly journals Removal of COD and SO42− from Oil Refinery Wastewater Using a Photo-Catalytic System—Comparing TiO2 and Zeolite Efficiencies

Water ◽  
2020 ◽  
Vol 12 (1) ◽  
pp. 214 ◽  
Author(s):  
Emmanuel K. Tetteh ◽  
Elorm Obotey Ezugbe ◽  
Sudesh Rathilal ◽  
Dennis Asante-Sackey
Keyword(s):  
Reaction Time ◽  
Catalytic System ◽  
Uv Light ◽  
Operating Conditions ◽  
Oil Refinery ◽  
Interactive Effects ◽  
Refinery Wastewater ◽  
Mixing Rate ◽  
Water And Wastewater Treatment ◽  
Oil Refinery Wastewater

Advanced oxidation processes (AOPs) have many prospects in water and wastewater treatment. In recent years, AOPs are gaining attention as having potentials for the removal of different ranges of contaminants from industrial wastewater towards water reclamation. In this study, the treatability efficiencies of two photo-catalysts (TiO2 and zeolite) were compared on the basis of the removal of chemical oxygen demand (COD) and SO42− from oil refinery wastewater (ORW) using photo-catalytic system. The effects of three operating parameters: catalyst dosage (0.5–1.5 g/L), reaction time (15–45 min), mixing rate (30–90 rpm) and their interactive effects on the removal of the aforementioned contaminants were studied using the Box–Behnken design (BBD) of response surface methodology (RSM). Statistical models were developed and used to optimize the operating conditions. An 18 W UV light was incident on the system to excite the catalysts to trigger a reaction that led to the degradation and subsequent removal of contaminants. The results obtained showed that for almost the same desirability (92% for zeolite and 91% for TiO2), TiO2 exhibited more efficiency in terms of mixing rate and reaction time requirements. At the 95% confidence level, the model’s predicted results were in good agreement with experimental data obtained.

scholarly journals Independent and interactive effects of thermal stress and mental fatigue on manual dexterity

2020 ◽  
Vol 319 (6) ◽  
pp. R703-R711
Author(s):  
Alessandro Valenza ◽  
Harry Charlier ◽  
Antonino Bianco ◽  
Davide Filingeri
Keyword(s):  
Thermal Stress ◽  
Reaction Time ◽  
Interactive Effect ◽  
Thermal Conditions ◽  
Mental Fatigue ◽  
Manual Dexterity ◽  
Interactive Effects ◽  
Manual Task ◽  
Air Temperatures ◽  
Manual Tasks

Many occupations and sports require high levels of manual dexterity under thermal stress and mental fatigue. Yet, multistressor studies remain scarce. We quantified the interactive effects of thermal stress and mental fatigue on manual dexterity. Seven males (21.1 ± 1.3 yr) underwent six separate 60-min trials characterized by a combination of three air temperatures (hot, 37°C; neutral, 21°C; cold, 7°C) and two mental fatigue states (MF, mental fatigue induced by a 35-min cognitive battery; no-MF, no mental fatigue). Participants performed complex (O’Connor test) and simple (hand-tool test) manual tasks pre- and posttrial to determine stressor-induced performance changes. We monitored participants’ rectal temperature and hand skin temperature (Thand) continuously and assessed the reaction time (hand-click test) and subjective mental fatigue (5-point scale). Thermal stress ( P < 0.0001), but not mental fatigue ( P = 0.290), modulated Thand (heat, +3.3°C [95% CI: +0.2, +6.5]; cold, −7.5°C [−10.7, −4.4]). Mental fatigue ( P = 0.021), but not thermal stress ( P = 0.646), slowed the reaction time (∼10%) and increased subjective fatigue. Thermal stress and mental fatigue had an interactive effect on the complex manual task ( P = 0.040), with cold-no-MF decreasing the performance by −22% [−39, −5], whereas neutral-MF, cold-MF, and heat-MF by −36% [−53, −19], −34% [−52, −17], and −36% [−53, −19], respectively. Only mental fatigue decreased the performance in the simple manual task (−30% [−43, −16] across all thermal conditions; P = 0.002). Cold stress-induced impairments in complex manipulation increase with mental fatigue; yet combined stressors’ effects are no greater than those of mental fatigue alone, which also impairs simple manipulation. Mental fatigue poses a greater challenge to manual dexterity than thermal stress.

Optimization of Linoleic Acid Monoepoxidation Condition from Malaysian Jatropha curcas Using Central Composite Design (CCD)

2015 ◽  
Vol 754-755 ◽  
pp. 1107-1112
Author(s):  
Rozaini Abdullah ◽  
Jumat Salimon ◽  
Anis Atikah Ahmad
Keyword(s):  
Linoleic Acid ◽  
Reaction Time ◽  
Experimental Design ◽  
Central Composite Design ◽  
Reaction Temperature ◽  
Jatropha Curcas ◽  
Catalyst Loading ◽  
Time Saving ◽  
Independent Variable ◽  
Central Composite

The aim of this study was to optimize the monoepoxidation process of linoleic acid obtained from Malaysian Jatropha curcas oil using central composite design (CCD). There were four independent variable factors had been studied which involved reaction temperature (X1), reaction time (X2), catalyst loading (X3) and H2O2 concentration (X4). Thirty experiments were carried out based on the experimental design responses obtained. The results showed that the optimum condition was obtained at catalyst loading of 0.11% (w/w) methyltrioxorhernium (VII) (MTO), H2O2 mole of 99%, reaction temperature of 58.41oC for 5 hours. The central composite design was proven to be simpler method, time saving and required less samples compared to the conventional method.

Optimization of Synthesis Technology of Acetylferrocene by Response Surface Methodology

2012 ◽  
Vol 622-623 ◽  
pp. 162-165
Author(s):  
Da Wei Yin ◽  
Gang Tao Liang ◽  
Xiao Ming Sun ◽  
Yu Ting Liu
Keyword(s):  
Response Surface Methodology ◽  
Reaction Time ◽  
Response Surface ◽  
Acetyl Chloride ◽  
Raw Materials ◽  
Raw Material ◽  
Interactive Effects ◽  
Percentage Yield ◽  
Experimental Yield ◽  
Central Composite

Acetylferrocene was synthesized by acetyl chloride and ferrocene as raw materials, dichloromethane as the solvent, and ZnO as catalyst. Response surface methodology based on three-level, three-variable central composite rotable design was used to evaluate the interactive effects of the ratio of acetyl chloride and ferrocene(2-4), the amount of ZnO(1.0-1.3mol), reaction time(30-60 min)on the percentage yield of acylferrocene. The optimal raw material ratio, amount catalyst, and reaction time was 3:1, 1.19mol, 40min. Under the optimum conditions, the actual experimental yield can reach 86.72%.

Interactive Effects of Physical Attractiveness in Advertisements

1998 ◽  
Vol 82 (3_suppl) ◽  
pp. 1403-1410 ◽  
Author(s):  
Takayoshi Onodera ◽  
Masaki Miura
Keyword(s):  
Experimental Design ◽  
Undergraduate Students ◽  
Physical Attractiveness ◽  
Interactive Effects ◽  
Consistent Difference ◽  
Women Subjects

Interactive effects between the physical attractiveness of models and the attributes of advertisements were investigated with 186 undergraduate students. We hypothesized that, while an attractive model would be judged to be appropriate for the advertisement for feminine types of products, an unattractive model would be perceived to be appropriate for the advertisement of masculine types of products. As a feminine type of product and a masculine type of product, we used a diet drink and stamina drink. Each drink was considered appropriate for each sex in Japan. The experimental design was 3 (attractive model/no model/unattractive model) x 2 (drink for women/drink for men) x 2 (sex of subjects). Being presented a fabricated drink advertisement with a photograph of the model, the subjects were asked to evaluate the same points, including appropriateness, for the model, products and advertisement. Analysis supported the interactive hypothesis only concerning women subjects. It is suggested that there is a consistent difference in perception by sex group in Japan.

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