scholarly journals The Effects of Driving Environment on the Mental Workload of Train Drivers

2013 ◽  
Vol 10 ◽  
pp. 93-99
Author(s):  
Nurul Izzah Abd Rahman ◽  
Siti Zawiah Md. Dawal ◽  
Ardeshir Bahreininejad

A study is carried out to investigate the effects of driving environment on the mental workload of train drivers while driving. The driving task is performed under three environmental conditions, i.e. clear sunny day, rainy day and rainy night driving. Electroencephalography (EEG) measurements are recorded from the Fz and Pz channels of fifteen male subjects aged between 24 to 48 years old. The mean alpha power is monitored as a function of time as this signal reflects the variations in mental workload of the drivers. The results exhibit that the signal pattern for rainy night driving condition is significantly different compared to others. This finding indicates that the train drivers show an increase in mental workload after six minutes of driving under rainy night condition. The results demonstrate a percentage difference in mean alpha power of 37% between daytime and rainy night driving conditions during the early periods of driving. This indicates that the mental workload of train drivers tends to be low with an increased level of sleepiness under such conditions, which are signs of low vigilance.

1973 ◽  
Vol 72 (2) ◽  
pp. 265-271 ◽  
Author(s):  
J. H. Dussault ◽  
D. A. Fisher ◽  
J. T. Nicoloff ◽  
V. V. Row ◽  
R. Volpe

ABSTRACT In order to determine the effect of alterations in binding capacity of thyroxine binding globulin (TBG) on triiodothyronine (T3) metabolism, studies were conducted in 10 patients with idiopathically low (7 subjects) or elevated (3 subjects) TBG levels and 10 subjects given norethandrolone (7 male subjects) or oestrogen (3 female subjects). Measurements of serum thyroxine (T4) concentration, maximal T4 binding capacity, serum T3 concentration and per cent dialyzable T3 were conducted. Serum T3 was measured both by chemical and radioimmunoassay methods. In patients with idiopathically low TBG, the mean serum T4 concentration was low (2.4 μg/100 ml), the mean serum T3 level low (55 ng/100 ml), the mean per cent dialyzable T3 increased (0.52%), and the calculated free T3 concentration normal (186 pg/100 ml). In patients with idiopathically high TBG levels the mean T4 concentration was high (10.3 μg/100 ml), the mean T3 level slightly elevated (127 ng/100 ml), the% dialyzable T3 low (0.10%) and the calculated free T3 concentration low normal (123 pg/100 ml). The correlation coefficient between the per cent dialyzable T3 and maximal TBG binding capacity in the 20 subjects was 0.68, a value significant at the P < 0.01 level. Thus, alterations in binding capacity of TBG seem to influence T3 and T4 metabolism similarly; the inverse relationship between the % of dialyzable hormone and total hormone concentration tends to keep the absolue levels of free hormones stable.


2019 ◽  
Vol 2 (3) ◽  
Author(s):  
Kartiani Dewi ◽  
Suryani S ◽  
Ahmad Yamin

Lecturers are responsible for implementing the three main responsibilities in university (Tridharma Perguruan Tinggi) with 12 credits to 16 credits each semester. However, many lecturers feel that the workload is very excessive. The purpose of this study was to describe the mental workload of lecturers at the Faculty of X Padjadjaran University. The method of this research was quantitative descriptive by using a total sampling technique involving 43 lecturers. Data collection used NASA-TLX instruments. Data were analysed using descriptive statistics. The results of the study showed that overall the mental workload of the Faculty of X Padjadjaran University lecturers was included in the high category both in education and teaching assignments (74.4%), research assignments (76.7%), and community service assignments (74.4%). ) Effort dimensions have the highest mean value that is equal to 51.8, while the dimensions that have the lowest mean are Perfomance dimension, namely 9.4, where the greater the mean dimension shows the large contribution in the mental workload felt by the lecturer. The conclusions, this study show that most lecturers have a high mental workload. It is suggested that the lecturers need to have balance numbers of tasks according to their abilities, balance the time working with recreation, and meet the needs of rest. The results of this study need to be followed up by examining methods or efforts that can reduce the lecturers' mental workload.


Author(s):  
Ruta R. Sardesai ◽  
Thomas M. Gable ◽  
Bruce N. Walker

Using auditory menus on a mobile device has been studied in depth with standard flicking, as well as wheeling and tapping interactions. Here, we introduce and evaluate a new type of interaction with auditory menus, intended to speed up movement through a list. This multimodal “sliding index” was compared to use of the standard flicking interaction on a phone, while the user was also engaged in a driving task. The sliding index was found to require less mental workload than flicking. What’s more, the way participants used the sliding index technique modulated their preferences, including their reactions to the presence of audio cues. Follow-on work should study how sliding index use evolves with practice.


2006 ◽  
Vol 1 (3) ◽  
pp. 57
Author(s):  
Suzanne Pamela Lewis

A review of: Antelman, Kristin. “Do Open-Access Articles Have a Greater Research Impact?” College & Research Libraries 65.5 (Sep. 2004): 372-82. Objective – To ascertain whether open access articles have a greater research impact than articles not freely available, as measured by citations in the ISI Web of Science database. Design – Analysis of mean citation rates of a sample population of journal articles across four disciplines. Setting – Journal literature across the disciplines of philosophy, political science, mathematics, and electrical and electronic engineering. Subjects – A sample of 2,017 articles across the four disciplines published between 2001 and 2002 (for political science, mathematics, and electrical and electronic engineering) and between 1999 and 2000 (for philosophy). Methods – A systematic presample of articles for each of the disciplines was taken to calculate the necessary sample sizes. Based on this calculation, articles were sourced from ten leading journals in each discipline. The leading journals in political science, mathematics, and electrical and electronic engineering were defined by ISI’s Journal Citation Reports for 2002. The ten leading philosophy journals were selected using a combination of other methods. Once the sample population had been identified, each article title and the number of citations to each article (in the ISI Web of Science database) were recorded. Then the article title was searched in Google and if any freely available full text version was found, the article was classified as open access. The mean citation rate for open access and non-open access articles in each discipline was identified, and the percentage difference between the means was calculated. Main results – The four disciplines represented a range of open access uptake: 17% of articles in philosophy were open access, 29% in political science, 37% in electrical and electronic engineering, and 69% in mathematics. There was a significant difference in the mean citation rates for open access articles and non-open access articles in all four disciplines. The percentage difference in means was 45% in philosophy, 51% in electrical and electronic engineering, 86% in political science, and 91% in mathematics. Mathematics had the highest rate of open access availability of articles, but political science had the greatest difference in mean citation rates, suggesting there are other, discipline-specific factors apart from rate of open access uptake affecting research impact. Conclusion – The finding that, across these four disciplines, open access articles have a greater research impact than non-open access articles, is only one aspect of the complex changes that are presently taking place in scholarly publishing and communication. However, it is useful information for librarians formulating strategies for building institutional repositories, or exploring open access publishing with patrons or publishers.


Fractals ◽  
1993 ◽  
Vol 01 (01) ◽  
pp. 11-19 ◽  
Author(s):  
SHU MATSUURA ◽  
SASUKE MIYAZIMA

A variety of colony shapes of the fungus Aspergillus oryzae under varying environmental conditions such as the nutrient concentration, medium stiffness and incubation temperature are obtained, ranging from a homogeneous Eden-like to a ramified DLA-like pattern. The roughness σ(l, h) of the growth front of the band-shaped colony, where h is the mean front height within l of the horizontal range, satisfies the self-affine fractal relation under favorable environmental conditions. In the most favorable condition of our experiments, its characteristic exponent is found to be a little larger than that of the 2-dimensional Eden model.


1983 ◽  
Vol 61 (8) ◽  
pp. 2212-2223 ◽  
Author(s):  
Catherine Damerval

Seven foliar types were defined for the first leaf in the heteroblastic development of seven annual species of Medicago L. Among the species, M. aculeata and M. murex have a typical foliar form. There is no relation between the first leaf and the succeeding trifoliolate one. The shape changes of the middle foliole of the trifoliolate leaves during the development allowed to establish a foliar sequence whose mean length was used to suggest an evolutive hierarchy among the taxa. Five quantitative variables were analysed on the first and on the sixth leaf for stability according to environmental conditions; the two stable variables (L/l and L/Pl) have a best discriminant value for the first leaf than for the sixth one. However, intraspecific heterogeneity is high in both cases. A relation between the flowering precocity and the mean value of one of the sixth leaf's variables (that is, the ratio of the length to the width of the foliole limb) was demonstrated in four species only. The heteroblastic development not only allows to establish a relation between foliar stage and physiologic age, but it itself constitutes a very good taxonomic and systematic criterium; it allowed to identify the seven species studied.


1988 ◽  
Vol 22 (3) ◽  
pp. 202-204 ◽  
Author(s):  
Merlin V. Nelson ◽  
Vickie Tutag-Lehr ◽  
R. Lee Evans

Nine normal, healthy male subjects had significantly elevated thyroid-stimulating hormone (TSH) concentrations while receiving oral lithium carbonate for two weeks. The mean minimum lithium serum concentration was 0.765 mEq/L. The TSH concentrations after 15 days on lithium were significantly correlated to the TSH concentration at baseline. No correlation was found between mean minimum lithium steady-state concentration and TSH concentration after 15 days on lithium. Further research is necessary to determine if a high baseline TSH concentration or an early rise in TSH will predict those patients who will eventually develop hypothyroidism after long-term lithium therapy.


Author(s):  
Abdullah F. Serheed ◽  
Haider T. Hussein

Afield experiment was carried out during the spring and autumn seasons of 2016 and 2017 in AL- Musaib city / 40 km north of Babylon Provence. Two hybrids of sunflower( shamus, French hybrid (Euroflor) were used to evaluate the performance of the two cultivars at both growing seasons as well as knowledge of genetic behavior by studying the genetic and phenotypic variations, heritability percent, genetic and phenotypic coefficient, stability and persistence of the two cultivars .The results showed significant differences of the studied traits, as the genetic genotype (Shamus) most of the characteristics, especially in yield for two seasons.The genetic variance was higher than the environmental variance for the two seasons indicating that the two cultivars followed the same behavior. The heritability percent the dominant sense was high for most of the traits. The genetic and phenotypic variations between the mean and the high were different for the two seasons, the correlation coefficient was significant, for both cultivars, indicating the appropriateness of the two genotypes for the country's environmental conditions.


1962 ◽  
Vol 40 (1) ◽  
pp. 1515-1527
Author(s):  
Claude Allard ◽  
Gaston Choquette

A relatively rapid procedure for the routine estimation of lipoproteins in prestained human sera by zone electrophoresis in paper was described. This technique was employed for the study of the percentage of alpha-lipoproteins in sera of healthy and coronary male subjects of various ages. The mean proportion of alpha-lipoproteins in healthy males (100) was observed to be about 24% in subjects at the age of 20–29 and 16% at the age of 30–59. In the coronary group (105) the mean percentage of alpha-lipoproteins was lower than 13% irrespective of age. From this study, the diagnostic value of alpha-lipoproteins percentage to characterize a coronary patient appeared to be superior to total cholesterol concentrations.


Author(s):  
Amy S. McDonnell ◽  
Trent G. Simmons ◽  
Gus G. Erickson ◽  
Monika Lohani ◽  
Joel M. Cooper ◽  
...  

Objective This research explores the effect of partial vehicle automation on neural indices of mental workload and visual engagement during on-road driving. Background There is concern that the introduction of automated technology in vehicles may lead to low driver stimulation and subsequent disengagement from the driving environment. Simulator-based studies have examined the effect of automation on a driver’s cognitive state, but it is unknown how the conclusions translate to on-road driving. Electroencephalographic (EEG) measures of frontal theta and parietal alpha can provide insight into a driver’s mental workload and visual engagement while driving under various conditions. Method EEG was recorded from 71 participants while driving on the roadway. We examined two age cohorts, on two different highway configurations, in four different vehicles, with partial vehicle automation both engaged and disengaged. Results Analysis of frontal theta and parietal alpha power revealed that there was no change in mental workload or visual engagement when driving manually compared with driving under partial vehicle automation. Conclusion Drivers new to the technology remained engaged with the driving environment when operating under partial vehicle automation. These findings suggest that the concern surrounding driver disengagement under vehicle automation may need to be tempered, at least for drivers new to the experience. Application These findings expand our understanding of the effects of partial vehicle automation on drivers’ cognitive states.


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