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- Brännmark, Mikael, et al.
(författare)
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Packages of participation : Swedish employees´experience of Lean depends on how they are involved
- 2013
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Ingår i: IIE Transactions on Occupational Ergonomics and Human Factors. - : Informa UK Limited. - 2157-7323 .- 2157-7331. ; 1:2, s. 93-108
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Tidskriftsartikel (refereegranskat)abstract
- Background: Lean production is a dominant approach in Swedish and global manufacturing and service industries. Studies of Lean’s employee effects are few and contradictory. Purpose: Employee effects from Lean are likely not uniform. This article investigates the effect of employees’ participation on their experiences of Lean. Method: This study investigated how different packages of employee participation in Lean affected manufacturing workers’ experiences of Lean. During 2008–2011, qualitative and quantitative data were collected from Swedish manufacturing companies participating in the national Swedish Lean production program Produktionslyftet. Data from 129 surveys (28 companies), 39 semi-structured interviews, and 30 reports were analyzed. In the main analysis, comparisons were made of the survey-reported Lean experiences of employees in three groups: temporary group employees (N = 36), who participated in Lean mostly through intermittent projects; continuous group employees (N = 69), who participated through standing improvement groups; and combined group employees (N = 24), who participated in both ways. Results: Continuous group employees had the most positive experience of Lean, followed by the combined group. Temporary group employees had the least positive experiences, being less likely than their counterparts to report that Lean improved teamwork; occupational safety; and change-related learning, decision making, and authority. Conclusions: These findings support the importance of continuous, structured opportunities for participation but raise the possibility that more participation may result in greater workload and role overload, mitigating some benefits of employee involvement. Consequently, companies should consider involving employees in change efforts but should attend to the specific design of participation activities.
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| 2. |
- Richter, Hans, 1961-, et al.
(författare)
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Near-Infrared Spectroscopy as a Useful Research Tool to Measure Prefrontal Cortex Activity During Visually Demanding Near Work
- 2016
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Ingår i: IISE Transactions on Occupational Ergonomics and Human Factors. - : Taylor & Francis. - 2472-5838 .- 2472-5846 .- 2157-7323 .- 2157-7331. ; 4:2-3, s. 164-174
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Tidskriftsartikel (refereegranskat)abstract
- OCCUPATIONAL APPLICATIONS Effort, which overrides the need for rest and recuperation to avoid deterioration in visual performance, is commonplace in many contemporary workplaces. The prefrontal cortex is capable of allocating more mental/physical resources to carry out a given work task in the presence of fatigue. However, adverse musculoskeletal and mental health consequences are an anticipated outcome of this since fatigue is a physiological sign of the need for recuperative rest. This article outlines the current evidence suggesting that probing into prefrontal brain activity with near-infrared spectroscopy could advance progress in visual ergonomic research, and pilot data are provided that exemplify the proposed approach. Improved understanding of the age-related health consequences of straining the brain and/or the eyes "to see well" will likely help ergonomic stakeholders find better methods to meet the needs of safer and more productive work environments.TECHNICAL ABSTRACT Background: Unlike the usual skeletal muscles, ciliary muscles responsible for focusing the crystalline eye lens and extraocular muscles responsible for convergence eye movements appear resistant to fatigue. Purpose: The dual goals of this article are to briefly outline the current evidence that suggests that probing into blood flow and hemodynamic prefrontal brain activity with near-infrared spectroscopy could advance progress in visual ergonomic research and to provide pilot data exemplifying the proposed approach. Methods: The vision task consisted of sustained focusing on a contrast-varying black-and-white Gabor grating. Four participants with a median age of 46 (interquartile range 44-50) fixated the grating from a distance of 65 cm. Three counterbalanced 10-minute tasks required central fixation and accommodation/convergence on the grating target through (i) 0.0 diopter lenses, (ii) -1.5 diopter lenses, and (iii) -3.5 diopter lenses while maintaining maximal focus. Non-invasive measurements of local oxyhemoglobin (HbO(2)) were quantified with a one-channel near-infrared spectrometer. The near-infrared spectroscopy probe was placed on the prefrontal cortex in the vicinity of the right dorsolateral prefrontal cortex or Brodmann area 46. Accommodation response and contrast threshold were measured in parallel. Results: General estimating equation analyses showed that baseline-subtracted dorsolateral prefrontal cortex blood flow (Delta HbO(2)) increased significantly over time in all three lens conditions. The effect of time may be caused by a continuous increase in mental effort to compensate for progressively more mental fatigue induced by increased visual attention. The increase of dorsolateral prefrontal cortex Delta HbO(2) was also larger in magnitude in participants with larger amplitudes accommodation response (i.e., in participants who minimized deterioration in visual performance). Conclusion: The results from this study indicate that oxyhemoglobin changes recorded over the dorsolateral prefrontal cortex with near-infrared spectroscopy can be used to assay the degree to which the visual system is strained during demanding near work.
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