scholarly journals Effect of High-Altitude Environment on Driving Safety: A Study on Drivers’ Mental Workload, Situation Awareness, and Driving Behaviour

2020 ◽  
Vol 2020 ◽  
pp. 1-10
Author(s):  
Xinyan Wang ◽  
Wu Bo ◽  
Weihua Yang ◽  
Suping Cui ◽  
Pengzi Chu
Keyword(s):  
High Altitude ◽  
Situation Awareness ◽  
Mental Workload ◽  
Mediating Effect ◽  
Driving Safety ◽  
Risky Driving ◽  
Driving Behaviour ◽  
Driving Risk ◽  
Low Altitude ◽  
The Relationship

This study aims to analyze the effect of high-altitude environment on drivers’ mental workload (MW), situation awareness (SA), and driving behaviour (DB), and to explore the relationship among those driving performances. Based on a survey, the data of 356 lowlanders engaging in driving activities at Tibetan Plateau (high-altitude group) and 341 lowlanders engaging in driving activities at low altitudes (low-altitude group) were compared and analyzed. The results suggest that the differences between the two groups are noteworthy. Mental workload of high-altitude group is significantly higher than that of low-altitude group, and their situation awareness is lower significantly. The possibility of risky driving behaviours for high-altitude group, especially aggressive violations, is higher. For the high-altitude group, the increase of mental workload can lead to an increase on aggressive violations, and the situation understanding plays a full mediating effect between mental workload and aggressive violations. Measures aiming at the improvement of situation awareness and the reduction of mental workload can effectively reduce the driving risk from high-altitude environment for lowlanders.

scholarly journals Testing for local adaptation and evolutionary potential along 1 altitudinal gradients in rainforest Drosophila: beyond laboratory estimates

2016 ◽  
Author(s):  
Eleanor K. O’Brien ◽  
Megan Higgie ◽  
Alan Reynolds ◽  
Ary A. Hoffmann ◽  
Jon R. Bridle
Keyword(s):  
Genetic Variation ◽  
Environmental Change ◽  
High Altitude ◽  
Local Adaptation ◽  
Biotic Interactions ◽  
Environmental Variation ◽  
Species Range ◽  
Altitudinal Gradients ◽  
Low Altitude ◽  
The Relationship

ABSTRACTPredicting how species will respond to the rapid climatic changes predicted this century is an urgent task. Species Distribution Models (SDMs) use the current relationship between environmental variation and species’ abundances to predict the effect of future environmental change on their distributions. However, two common assumptions of SDMs are likely to be violated in many cases: (1) that the relationship of environment with abundance or fitness is constant throughout a species’ range and will remain so in future, and (2) that abiotic factors (e.g. temperature, humidity) determine species’ distributions. We test these assumptions by relating field abundance of the rainforest fruit fly Drosophila birchii to ecological change across gradients that include its low and high altitudinal limits. We then test how such ecological variation affects the fitness of 35 D. birchii families transplanted in 591 cages to sites along two altitudinal gradients, to determine whether genetic variation in fitness responses could facilitate future adaptation to environmental change. Overall, field abundance was highest at cooler, high altitude sites, and declined towards warmer, low altitude sites. By contrast, cage fitness (productivity) increased towards warmer, lower altitude sites, suggesting that biotic interactions (absent from cages) drive ecological limits at warmer margins. In addition, the relationship between environmental variation and abundance varied significantly among gradients, indicating divergence in ecological niche across the species’ range. However, there was no evidence for local adaptation within gradients, despite greater productivity of high altitude than low altitude populations when families were reared under laboratory conditions. Families also responded similarly to transplantation along gradients, providing no evidence for fitness trade-offs that would favour local adaptation. These findings highlight the importance of (1) measuring genetic variation of key traits under ecologically relevant conditions, and (2) considering the effect of biotic interactions when predicting species’ responses to environmental change.

The Relationship between Mental Workload and Situation Awareness

2000 ◽  
Vol 44 (21) ◽  
pp. 3-460-3-463 ◽  
Author(s):  
Michael A. Vidulich
Keyword(s):  
Cognitive Processing ◽  
Situation Awareness ◽  
Mental Workload ◽  
Processing Abilities ◽  
Common Goals ◽  
Two Measures ◽  
The Cost ◽  
The Relationship ◽  
Simple Fashion ◽  
Empirical Database

Mental workload and situation awareness are both outgrowths of the practical need to assess operators' performing and managing dynamic complex tasks. Mental workload refers to the cost placed on the human operator's cognitive processing abilities by performing the required task-related mental processing. Situation awareness is the operator's apprehension of the current situation. Common goals of designing a new system or modifying an existing one are often to reduce the operator's mental workload while increasing the operator's situation awareness. However, the empirical database obtained from concurrent evaluation of mental workload and situation awareness demonstrates that the two measures generally do not co-vary in such a simple fashion. The lack of a single straightforward correlation could be interpreted as an indication that mental workload and situation awareness must be considered independent of each other. However, parsing the available studies into sub-categories based on the type of manipulation that was investigated allows some possible relationships between mental workload and situation awareness to emerge. This suggests that researchers should continue to examine the relationship between these concepts and system evaluators should not consider mental workload or situation awareness in isolation from the other.

The Mediating Effect of Organizational Culture, Size, and Structure on the Relationship between Innovations and Resilience in Selected Nigerian Universities

2017 ◽  
pp. 993-1033
Author(s):  
Levi Uche Ahiauzu ◽  
Nwachukwu Prince Ololube
Keyword(s):  
Organizational Culture ◽  
Adaptive Capacity ◽  
Situation Awareness ◽  
Mediating Effect ◽  
Chi Square ◽  
Descriptive Research ◽  
Vice Chancellors ◽  
The Relationship ◽  
Innovation Impact ◽  
Size And Structure

This chapter empirically investigated the mediating effect of organizational culture, size and structure on the relationship between innovations and resilience in selected Nigerian universities. The descriptive research design was adopted. The respondents comprised Heads of Departments, Deans of Faculties, Directors, Registrars and Deputy Registrars, and Vice Chancellors and Deputy Vice Chancellors. The analyses of the data involved the use of multiple statistical procedures: Percentages, Mean, Chi-square (hypotheses 1-6) and One-way Analysis of Variance (ANOVA). ANOVA was used to test hypotheses 7-12, using the statistical package for social sciences (SPSS) version 21. The research instrument was quantitatively analyzed and an overall Cronbach alpha coefficient of .845 was realized. In this study, we gathered that significant relationship exists between product innovation and situation awareness, keystone vulnerabilities and adaptive capacity. Process innovation impact on situation awareness, keystone vulnerabilities and adaptive capacity. In addition, relationships were found between administrative innovation and situation awareness, keystone vulnerabilities and adaptive capacity. Correspondingly, we found that organizational culture, size and structure has a significant moderating relationship between innovation and resilience. Nigeria universities like other developing counties universities need effective innovation programs.

scholarly journals Chronic Exposure to High Altitude and Job Burnout Among Chinese Military Personnel at Qinghai-Tibet Plateau: The Mediating Effect of Fatigue and Moderating Effect of Deployment Duration

2020 ◽  
Author(s):  
Zhi-hao Tu ◽  
Li Peng ◽  
Jing-wen He ◽  
Xing-hua Shen
Keyword(s):  
High Altitude ◽  
Military Personnel ◽  
Chronic Exposure ◽  
Ordinary Least Squares ◽  
Moderating Effect ◽  
Job Burnout ◽  
Mediating Effect ◽  
Tibet Plateau ◽  
Chinese Military ◽  
Low Altitude

Abstract Background: Job burnout among military personnel is associated with many negative consequence including depression, various forms of job withdrawal, and poor job performance. The present study aimed to investigate how chronic exposure to HA, fatigue, and deployment duration may influence burnout among Chinese military personnel. Methods: Military plateau drivers at Golmud (average altitude: 2,890m) as high altitude group (N = 194) and military drivers at Fuzhou (average altitude: 84m) as low altitude group (N = 190) completed the self-administrated questionnaires. Path analysis with ordinary least squares regression procedures were used to test the mediating effect of fatigue and moderating effect of deployment duration.Results: A simple mediation from altitude to burnout through fatigue was supported by the results. Military personnel at high altitude experienced severer fatigue than those at low altitude (B = 1.215, t = 4.303, p < 0.001), and fatigue in turn caused greater job burnout (B = 0.347, t = 6.132, p < 0.001). The mediating effect of fatigue was significant (M = 0.421, Boot LLCI = 0.207, Boot ULCI = 0.668) and explained 15.21% of the total effect of altitude on burnout. However, the moderating effects of deployment duration were not supported in the present study. Conclusion: The problem of job burnout among military personnel on the plateau may be diminished by relieving their mental and physical fatigue induced by chronic exposure to high altitude and increasing the number of vacation days away from plateau.

Depressed myocardial function in the goat at high altitude

1976 ◽  
Vol 41 (3) ◽  
pp. 356-361 ◽  
Author(s):  
C. E. Tucker ◽  
W. E. James ◽  
M. A. Berry ◽  
C. J. Johnstone ◽  
R. F. Grover
Keyword(s):  
High Altitude ◽  
Hypobaric Hypoxia ◽  
Chronic Hypoxia ◽  
Myocardial Function ◽  
Left Ventricular ◽  
Cardiac Performance ◽  
Left Ventricular Cavity ◽  
Wave Form ◽  
Low Altitude ◽  
The Relationship

To determine if depressed myocardial function contributes to the reported decrease in cardiac performance at high altitude, six chronically instrumented, unsedated goats were studied before, during, and after 2-wk exposureto hypobaric hypoxia (PaO2 44 mmHg). Undistorted ventricular pressure wave form was obtained from a miniature transducer implanted in the left ventricular cavity. The relationship between (dP/dt)/28P and P was extrapolated toobtain Vmax as an index of myocardial function. With beta sympathetic blockade (practolol) and pacing to reproduce heart rates, Vmax was uniformly andsignificantly depressed (P less than 0.01) during chronic hypoxia, and returned to control values following descent to low altitude. Likewise, stroke volume following saline infusion was decreased at high altitude and returned to control values following descent. Acute relief of hypoxia at high altitude by administration of 100% oxygen by mask did not reverse the depressedVmax. These findings indicate that chronic hypobaric hypoxia produces a depression of myocardial function which is reversible by chronic but not acuterelief of hypoxia.

scholarly journals Cognitive Biases, Risk Perception, and Risky Driving Behaviour

2021 ◽  
Vol 14 (1) ◽  
pp. 77
Author(s):  
Cornelia Măirean ◽  
Grigore M. Havârneanu ◽  
Danijela Barić ◽  
Corneliu Havârneanu
Keyword(s):  
Risk Perception ◽  
Traffic Safety ◽  
Cognitive Biases ◽  
Illusion Of Control ◽  
Future Research ◽  
Risky Behaviour ◽  
Risky Driving ◽  
Optimism Bias ◽  
Driving Behaviour ◽  
The Relationship

This study evaluated the relationship between drivers’ cognitive biases (i.e., optimism bias, illusion of control) and risky driving behaviour. It also investigated the mediational role of risk perception in the relationship between cognitive biases and self-reported risky driving. The sample included 366 drivers (Mage = 39.13, SD = 13.63 years) who completed scales measuring optimism bias, illusion of control, risk perception, and risky driving behaviour, as well as demographic information. The results showed that risky driving behaviour was negatively predicted by optimism bias and positively predicted by the illusion of control. Further, risk perception negatively correlated with risky behaviour and also mediated the relation between both optimism bias and illusion of control with risky driving. The practical implications of these results for traffic safety and future research are discussed.

The Mediating Effect of Organizational Culture, Size, and Structure on the Relationship Between Innovations and Resilience in Selected Nigerian Universities

2016 ◽  
pp. 327-364 ◽  
Author(s):  
Levi Uche Ahiauzu ◽  
Nwachukwu Prince Ololube
Keyword(s):  
Organizational Culture ◽  
Adaptive Capacity ◽  
Situation Awareness ◽  
Mediating Effect ◽  
Chi Square ◽  
Descriptive Research ◽  
Vice Chancellors ◽  
The Relationship ◽  
Innovation Impact ◽  
Size And Structure

This chapter empirically investigated the mediating effect of organizational culture, size and structure on the relationship between innovations and resilience in selected Nigerian universities. The descriptive research design was adopted. The respondents comprised Heads of Departments, Deans of Faculties, Directors, Registrars and Deputy Registrars, and Vice Chancellors and Deputy Vice Chancellors. The analyses of the data involved the use of multiple statistical procedures: Percentages, Mean, Chi-square (hypotheses 1-6) and One-way Analysis of Variance (ANOVA). ANOVA was used to test hypotheses 7-12, using the statistical package for social sciences (SPSS) version 21. The research instrument was quantitatively analyzed and an overall Cronbach alpha coefficient of .845 was realized. In this study, we gathered that significant relationship exists between product innovation and situation awareness, keystone vulnerabilities and adaptive capacity. Process innovation impact on situation awareness, keystone vulnerabilities and adaptive capacity. In addition, relationships were found between administrative innovation and situation awareness, keystone vulnerabilities and adaptive capacity. Correspondingly, we found that organizational culture, size and structure has a significant moderating relationship between innovation and resilience. Nigeria universities like other developing counties universities need effective innovation programs.

scholarly journals A Comparative Analysis of SARS-CoV-2 Viral Load Across Different Altitudes

2021 ◽  
Author(s):  
Esteban Ortiz-Prado ◽  
Raul Fernandez-Naranjo ◽  
Jorge Eduardo Vásconez ◽  
Alexander Paolo Vallejo-Janeta ◽  
Ismar A Rivera-Olivero ◽  
...  
Keyword(s):  
Viral Load ◽  
High Altitude ◽  
Male Gender ◽  
P Value ◽  
Altitude Range ◽  
High Altitudes ◽  
Low Altitude ◽  
The Relationship ◽  
Very High ◽  
Altitude Level

Abstract Background: SARS-CoV-2 has spread throughout the world, including areas located at high or very high altitudes. There is a debate about the role of high altitude hypoxia on viral transmission, incidence, and COVID-19 related mortality. This is the first comparison of SARS-CoV-2 viral load across elevations ranging from 0 to 4,300 m.Objective: To describe the SARS-CoV-2 viral load across samples coming from 62 cities located at low, moderate, high, and very high altitudes in Ecuador.Methodology: An observational analysis of viral loads among nasopharyngeal swap samples coming from a cohort of 4,929 patients with a RT-qPCR test positive for SARS-CoV-2.Results: The relationship between high and low altitude only considering our sample of 4,929 persons is equal in both cases and not significative (p-value 0.19). In the case of low altitude, adding the gender variable to the analysis, it was possible to find a significative difference between female and male gender (p-value 0.068). Considering initially gender and then altitude, it was possible to find a significative difference between high and low altitude for male gender (p-value 0.065). There is not enough evidence to state that viral load is affected directly by altitude range but adding a new variable as sex in the analysis shows that the presence of new variables influences the relationship of altitude range and viral load.Conclusions: There is no evidence that viral load differs at altitude level when we consider only one measure. Using as reference the variable gender is possible to note that at low altitude there is a difference between female and male gender. There is not difference between gender at high altitude level. In the case of considering gender as reference variable, it was possible to find that high and low altitude are different for male gender an equal for female gender. Viral load not only depends on altitude range; it also is affected by other variables like sex.

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