The effects of alcohol dosing on driving performance on a closed course and in a driving simulator†

The effect of alcohol consumption on driving performance was examined in two studies. In the first, six subjects drove for two hours over a closed-loop, two-lane course. In the second, 12 subjects drove for two hours in a driving simulator. In both studies, target blood alcohol concentrations (BAC) were 000%, 007%, or 0-12%. Multiple measures of vehicle control, tracking and information processing were recorded. In general, the standard deviations of these measures increased as BAC increased. Differences in the results between the two studies were related to differences in facilities (i.e. closed course vs. driving simulator).     

A quantitative assessment of the effects of passive upper extremity exoskeletons on expert cardiovascular sonographers’ muscle activity and posture while performing transthoracic echocardiograms (TTE)

During scanning, sonographers often assume significant awkward postures which may lead to musculoskeletal pain and disability. Two exoskeletons were tested as an ergonomic intervention by sonographers during transthoracic echocardiograms (TTE). Four sonographers each performed TTEs using right- and left-handed scanning techniques, with and without two different passive upper extremity exoskeletons in two two-by-two experimental designs. Posture, muscle activity, and subjective discomfort scores were recorded. Of the two exoskeletons tested, the updated FLEX® design significantly reduced 10th percentile upper trapezius muscle activity during left hand scanning, while the AIRFRAME® did not impact muscle activity across all the muscles of interest. Furthermore, there was a slight decrease in the self-reported discomfort levels in their wrist and hands associated with performing TTE when wearing Exos1 compared to baseline. However, participants experienced issues with comfort, limitations on their range of motion (ROM), and interference with tasks with both exoskeletons. Collectively, the results indicate that the tested exoskeleton designs provide minimal benefit for reducing upper extremity muscle workload during TTE ultrasonography tasks.     

Hairdressers’ shoulder load when blow-drying – Studying the effect of a new blow dryer design on arm inclination angle and muscle pain

During nine months, nineteen hairdressers every second/third month switched the use between a blow dryer with traditional design and one with a new design. The new blow dryer had the possibility to change between two opposite directed air flows. Every second/third month arm inclination angle and upper trapezius muscle activity were measured a whole workday, and during blow-drying in the laboratory. Pronounced upper arm elevation was reduced with the new blow dryer. The muscle activity of the upper trapezius was only reduced in the laboratory, and daily pain reports were not significantly influenced at all. The subjective rating of time use, functionality and heaviness was less favourable for the new blow dryer, with only three out of nineteen preferring the new dryer at the end of the study period. However, the design of the new dryer demanded a change of work technique that might have been conceived as problematic by the experienced hairdressers.Relevance to industryWe studied a new professional handheld blow dryer designed to allow less postures with elevated arms, addressing an import risk factor for work-related musculoskeletal problems. Hairdressers using this new dryer had less time with upper arm in pronounced elevation during blow-drying.     

Effects of agricultural quad bike driving on postural control during static,dynamic and functional tasks – A field study

BackgroundDriving a quad bike in a rural occupational setting is likely to expose the driver to various physical stimuli including whole-body vibration (WBV). These exposures may be linked to post-driving postural alterations which in turn could lead to an increased risk of spinal injury while undertaking manual material handling activities immediately following driving or falls while exiting from a vehicle.PurposeThe purpose of this study was to use a battery of postural tasks namely; bipedal and unipedal stance, limits of stability (LOS) and lifting task to assess how quad bike driving alters the postural control (PC) in a group of rural workers.MethodsThe PC, determined from centre of pressure (COP) displacements in a group of rural workers (n = 34), was evaluated at three time (T) periods, once (T-I) before the 30 min quad bike driving session on a typical New Zealand farm terrain and twice (T-II and T-III) immediately following driving, each time period lasted approximately 10 min later.ResultsThe results demonstrated a significant (p < 0.05) increase and decrease in the magnitude of the COP measures for the lifting task and unipedal stance respectively during both T-II and T-III periods. However significant (p < 0.05) increase in the magnitude COP measures of bipedal stance, and increase in the maximal stability limits (LOS) were demonstrated only in the T-III.ConclusionsThese results demonstrate both immediate and sustained alterations in the PC following a period of occupational vehicle driving. Also, the results demonstrate both a worsening and improvement in postural control during the performance of a battery of tasks. Observed adverse or facilitatory postural effects will require further laboratory based investigations in order to determine how such disparity can best be explained or challenged.Relevance to industryThe findings will inform ergonomists about the potential risk involved in carrying out physically demanding occupational tasks following vehicle driving. This putative situation could be prevented by adopting behavioural strategies by drivers, and engineered interventions designed to reduce WBV exposure.     

A comparative study of two wayfinding aids for simulated driving tasks – single-scale and dual-scale GPS aids

Global Positioning System (GPS) is currently the most frequently used wayfinding aid for driving. Yet, GPS is designed to act as a driving guide rather than to help users gain spatial knowledge. Accordingly, GPS might be less usable in situations where such knowledge is required or highly desirable. In this study, we experimentally study the influence of GPS display scales (single-scale vs. dual-scale) using simulated driving tasks in a virtual environment. The single-scale GPS is similar to the regular GPS view. The dual-scale GPS aid is a dual-scale navigation tool that provides two levels of detail, including both detailed and contextual information. The results demonstrate that the dual-scale GPS was more efficient in leading the participants to the destination during the simulated driving and was more useful for the participants to establish spatial awareness and a cognitive map; the dual-scale GPS participants also reported higher subjective evaluations. The proposed dual-scale GPS design and experimental results show some indications for designing new wayfinding aids aimed at increasing wayfinding performance while simultaneously helping users construct a cognitive map.     

A study on the relationships between different presentation modes of graphical icons and users’ attention

With the vigorous development of applications (App), graphical user interfaces (GUI) have been widely found in computers and handheld devices. This study aimed to explore the relationships between different presentation modes of graphical icons and users’ attention. An eye tracker was employed to measure each participant’s experimental data; in addition, subjective evaluation of attention was conducted. Thus, the optimum presentation mode attracting the most attention might be determined. The experiment was designed to investigate two variables: icon composition and background. Through permutation and combination, six presentation modes were obtained as follows: line + positive background (M1), plane + positive background (M2), line + negative background (M3), plane + negative background (M4), line + no background (M5), and plane + no background (M6). Thirty-six participants were requested to view thirty stimuli, or the contour drawings of graphical icons, presented simultaneously in six modes mentioned above. The participants’ fixation duration, fixation frequency, and subjective evaluation of attention were analyzed through two-way ANOVA. The analytical results showed that in terms of the three performance indicators above, M4 performed the best among the six presentation modes. Moreover, regarding icon composition, planes performed better than lines in terms of the three performance indicators. As for background, negative background performed the best in terms of the three performance indicators, positive background ranked second, and no background performed the worst. The findings can serve as a reference when icons are researched or designed in the future.     

The effect of online store atmosphere on consumer's emotional responses – an experimental study of music and colour

The current study is a convergence of two research orientations: the effect of ambient factors (e.g. music and colour) in physical stores and the website design in cyber context. The former emphasises the influence of sensory stimuli on the shoppers' responses; whereas the latter address the relationship between website design factors (e.g. usability) and the performance of a virtual store. This article aims to bridge the gap between the above research orientations and explores the impact of two environmental elements – music and colour – of an online store on the consumers' emotions – considered as direct antecedents to shopping behaviours – by employing a laboratory experiment. The results indicated that both music and colour reveal significant effects on respondents' emotional responses. To be more specific, participants felt more aroused and pleasant when they were under fast music and warm colour conditions than those who were exposed to an environment with slow music and cool colour. In addition, the congruency of these two atmospheric factors enhances the effects of atmosphere on people's emotional responses.     

The implications of serial correlation and time-lag effects for the impact study of climate change on vegetation dynamics – a case study with Hulunber meadow steppe,Inner Mongolia

Ecological time series data are widely used in ecological research thanks to the development of remote-sensing technologies and fixed ecological research stations. However, the serial correlation issue with time series, which violates the fundamental assumption of independence for traditional statistical models or analysis, is rarely considered by ecologists in vegetation–climate relationship research. In addition, the issue of time lags between climate change and vegetation response is also often ignored. Inadequate consideration of these issues produces misleading results in some cases. In this article, we propose an approach based on the Autoregressive Integrated Moving Average (ARIMA) model and the nonparametric test to address serial correlation issue and distribution requirements for the valid statistical analysis of time series data. With Hulunber meadow steppe as a case, we applied this approach to analyse the role of climate factors in vegetation dynamics based on leaf area index (LAI) data and climatic data. The results showed that the LAI dynamics of Hulunber meadow steppe were mainly related to temperature with the time lag of zero, whereas the impact of precipitation on LAI dynamics was not statistically obvious. The comparison of regression models that deal with serial correlation and residual normality to different extents showed that ignoring the serial correlation issue with time series data likely produces misleading results, highlighting the importance of serial correlation removal. The combination of nonparametric correlation tests with ARIMA-based cross-correlation analysis also proved quite useful in reducing the chance of spurious correlation and time lags resulting from outlier values in ARIMA-based cross-correlation.     

Daily impaired detachment and short-term effects of impaired sleep quality on next-day commuting near-accidents – an ambulatory diary study

This study investigated the short-term effects of daily recovery, that is, impaired psychological detachment from work and various actigraphical indicators of sleep quality, on near-accidents when commuting to work the next morning. Furthermore, the mediating effect of actigraphically assessed sleep quality on the relationship between impaired psychological detachment from work and near-accidents when commuting to work was analysed. Fifty-six full-time employees of a Swiss assurance company participated in the one-week study. Multilevel analyses revealed that impaired detachment was highly related to a decrease in sleep duration. Furthermore, impaired daily recovery processes, such as impaired psychological detachment from work and disturbed sleep quality, were related to commuting near-accidents. Impaired sleep quality mediated the effect of impaired psychological detachment from work on these near-accidents. Our results show that occupational safety interventions should address both impaired psychological detachment from work and sleep quality in order to prevent near accidents when commuting to work.

Practitioner Summary: Commuting accidents occur frequently and have detrimental effects on employees, organisations and society. This study shows that daily lack of recovery, that is, impaired psychological detachment and impaired sleep quality, is related to near-accidents when commuting to work the next morning. Primary prevention of commuting accidents should therefore address daily lack of recovery.     

The effects of a player’s network centrality on resource accessibility,game enjoyment,and continuance intention: A study on online gaming communities

This study applies social capital theory to investigate how a player’s network centrality in an online gaming community (i.e., a guild) affects his/her attitude and continuance intention toward a Massive Multiplayer Online Game (MMOG). Analysis of 347 usable responses shows that players’ network centrality has a negative impact on their ties to players who belong to other guilds (i.e., non-guild interaction), but a positive effect on players’ access to resources. However, players’ network centrality fails to increase their perceived game enjoyment directly. Players’ resource accessibility and perceived game enjoyment play mediating roles in the relationship between network centrality and attitude toward playing an MMOG, which in turn influences game continuance intention. The results also show that although players’ non-guild interaction is negatively related to their resource accessibility from the networks, it is positively associated with perceived game enjoyment. The article concludes with implications and limitations of the study.     

Conceptualizing task-technology fit and the effect on adoption – A case study of a digital textbook service

Although information technology has revolutionized virtually every aspect of how we interact with products and services, it has changed learning to a surprisingly small degree. In a study of a digital textbook service, we provide a new conceptual definition and measurement of technology fit. We conceptualize task-technology fit as how well a technology is integrated with a set of interrelated tasks included in achieving the goal of the behavior where the technology is used. Whereas research on technology adoption typically explains around 40 percent of the variance in motivation to adopt, our model explains as much as 76 percent.     

The role of work system-related factors on skilled workers’ turnover intentions – A study in small and medium-sized manufacturing enterprises in Southern Germany

Demographic change is leading to a substantial decline of the workforce and thus an increase in job vacancies in the labor market. This development favors employee turnover, which in particular is a challenge for manufacturing companies, for which it is already impossible to meet the demand for skilled workers. It is essential to identify specific predictors related to manufacturing that can lead to turnover, to define suitable countermeasures for retaining skilled employees in small and medium-sized (SME) manufacturing companies.This paper presents the results of a study conducted in manufacturing SMEs in Southern Germany. 11 companies and more than 240 skilled workers were surveyed. With regard to limitations, it cannot be completely excluded that there is a bias in participating companies. It is possible that the majority of the SMEs participated are concerned about the welfare of their employees anyway and companies with dissatisfied employees chose to decline participation. In addition, the sample size was limited due to the restrained participation rate, even if it was sufficient for the statistical tests.     

I spy with my AI: The effects of AI-based visual cueing on human operators’ performance and cognitive load in CCTV control rooms

The increased number of security cameras in modern cities has elevated the video-feed monitoring demands of closed-circuit television (CCTV) operators. As a result, new AI-driven support systems that leverage the power of computer vision algorithms have been deployed to facilitate the operators' work. However, to effectively design intuitive, AI-driven interfaces and validate their impact on the operators' performance, extensive user testing is required. To address this, we previously developed and tested a virtual reality (VR) control room that can be used to iteratively evaluate intelligent computer assistants and interfaces while operators are subjected to different cognitive load. In the present study, we use this VR environment and physiological markers (e.g., eye tracking measures) to investigate how AI-based visual cueing (i.e., pushing forward video streams on which detections are highlighted by rectangles drawn around targets) affects operator performance and cognitive load. Results suggest that support systems using such technology in a control room improve operators’ performance and decrease their cognitive load, as reflected by changes in pupil dilation and subjective reports irrespective of induced cognitive load.     

The impact of global dispersion on coordination,team performance and software quality – A systematic literature review

ContextGlobal software development (GSD) contains different context setting dimensions, which are essential for effective teamwork and success of projects. Although considerable research effort has been made in this area, as yet, no agreement has been reached about the impact of these dispersion dimensions on team coordination and project outcomes.ObjectiveThis paper summarizes empirical evidence on the impact of global dispersion dimensions on coordination, team performance and project outcomes.MethodWe performed a systematic literature review of 46 publications from 25 journals and 19 conference and workshop proceedings, which were published between 2001 and 2013. Thematic analysis was used to identify global dimensions and their measures. Vote counting was used to decide on the impact trends of dispersion dimensions on team performance and software quality.ResultsGlobal dispersion dimensions are consistently conceptualized, but quantified in many different ways. Different dispersion dimensions are associated with a distinct set of coordination challenges. Overall, geographical dispersion tends to have a negative impact on team performance and software quality. Temporal dispersion tends to have a negative impact on software quality, but its impact on team performance is inconsistent and can be explained by type of performance.ConclusionFor researchers, we reveal several opportunities for future research, such as coordination challenges in inter-organizational software projects, impact of processes and practices mismatches on project outcomes, evolution of coordination needs and mechanism over time and impact of dispersion dimensions on open source project outcomes. For practitioners, they should consider the tradeoff between cost and benefits while dispersing tasks, alignment impact of dispersion dimensions with individual and organizational objectives, coordination mechanisms as situational approaches and collocation of development activities of high quality demand components in GSD projects.     

Are you biting off more than you can chew? A case study on causes and effects of overscoping in large-scale software engineering

ContextScope management is a core part of software release management and often a key factor in releasing successful software products to the market. In a market-driven case, when only a few requirements are known a priori, the risk of overscoping may increase.ObjectiveThis paper reports on findings from a case study aimed at understanding overscoping in large-scale, market-driven software development projects, and how agile requirements engineering practices may affect this situation.MethodBased on a hypothesis of which factors that may be involved in an overscoping situation, semi-structured interviews were performed with nine practitioners at a large, market-driven software company. The results from the interviews were validated by six (other) practitioners at the case company via a questionnaire.ResultsThe results provide a detailed picture of overscoping as a phenomenon including a number of causes, root causes and effects, and indicate that overscoping is mainly caused by operating in a fast-moving market-driven domain and how this ever-changing inflow of requirements is managed. Weak awareness of overall goals, in combination with low development involvement in early phases, may contribute to ‘biting off’ more than a project can ‘chew’. Furthermore, overscoping may lead to a number of potentially serious and expensive consequences, including quality issues, delays and failure to meet customer expectations. Finally, the study indicates that overscoping occurs also when applying agile requirements engineering practices, though the overload is more manageable and perceived to result in less wasted effort when applying a continuous scope prioritization, in combination with gradual requirements detailing and a close cooperation within cross-functional teams.ConclusionThe results provide an increased understanding of scoping as a complex and continuous activity, including an analysis of the causes, effects, and a discussion on possible impact of agile requirements engineering practices to the issue of overscoping. The results presented in this paper can be used to identify potential factors to address in order to achieve a more realistic project scope.     

The pleasure of being (there?): an explorative study into the effects of presence and identification on the enjoyment of an interactive theatrical performance using omnidirectional video

This study explores how participants in an immersive theatrical performance perceive their role in the virtual environment (VE) and the effects of this perception on how they experience the performance as a whole. Using a quasi-experimental 2 × 2 design, narrative and task-based search was manipulated to explore the effects on spatial presence, social presence, identification and enjoyment. Results show that the effect of spatial presence on enjoyment of the performance is entirely mediated by identification with the role of the self in the VE. This could have interesting consequences for the experience of more narrative VE’s and suggests that the role of identification is something to explore further in future presence research.     

How agent heterogeneity,model structure and input data determine the performance of an empirical ABM – A real-world case study on residential mobility

Agent-based models (ABMs) have tended to become more complicated in recent years, going along with challenges of fully understanding model behaviour. While partly answered using simple and abstract models, the question of the role of different aspects of model detail for controlling model outcomes still has not been explored with empirical ABMs. We therefore use a detailed model built upon an empirical survey of residential mobility to explore the effects of three domains of model detail - agent heterogeneity, structural model detail and detail in the data used - on model performance. Evaluation is done by measuring the ability to predict empirical patterns for different topics, population, relocations and vacancies at different scales. Our diverse results indicate that a good data basis is crucial, heterogeneity strongly controls small-scale patterns and different design aspects must be tested thoroughly. This outcome calls for caution when interpreting the results of such models.     

The effect of different π-bridge configuration on bi-anchored triphenylamine and phenyl modified triphenylamine based dyes for dye sensitized solar cell (DSSC) application: A theoretical approach

Twenty eight bi-anchored triphenylamine (TH-1 to TH-14) and phenyl modified triphenylamine (PH-TH-1 to PH-TH-14) based metal free organic dyes are designed for DSSC application. The electronic effect of different π-bridge configurations in donor-π-bridge-acceptor (D-π-A)₂ structure was theoretically simulated and verified using density functional theory (DFT) and time dependent density functional theory (TD-DFT). The triphenylamine and phenyl modified triphenylamine groups are used as donor and cyanoacrylic acid group is used as acceptor. Thiophene and cyanovinyl groups are used as π-bridge. The ground state molecular structure was optimized by density functional theory and the electronic absorption spectra were calculated by time dependent density functional theory. The light harvesting efficiency (LHE), dye regeneration energy (ΔG_reg) and electron injection energy (ΔG_inject) are determined by computational examination. It is observed that, when the number of π-bridge increases, the band gap of the dye decreases. Also the absorption maximum and molar extinction coefficient of the dyes are increased. Theoretical result shows that the thiophene-cyanovinyl and thiophene-thiophene-cyanovinyl–cyanovinyl configurations give broader and red shifted absorption spectrum compared to other configurations. Also the results of phenyl modified triphenylamine (PH-TH) dyes clearly show better absorption and dye regeneration energy compared to TH dyes.