Different roles in the quest for system resilience

Into dangerous and complex systems with high degree of interactivity between its components, the variability is present at all time, demanding a high degree of control of its operation. Maintaining or recovering the normality, when the system is under some stress (instability) is a function of Resilience. To cope with prevention, forecast, recovery and with memory of experiences from learned lessons requires some features from the companies. This paper purposes a structure that enables the Total Resilience of a system production that defines the assignments for Workers, Designers and Management Team, according to its features and possibilities. During one year and a half developing studies on ergonomics area of a Brazilian Oil Refinery, several situations were observed and studied using Work Ergonomic Analysis. These situations show actions and strategies that workers use to maintain the system stability. Furthermore, they revealed the importance that these actions are stored in a database of learned lessons from the Company. The research resulted in a broad scheme. It places each of these groups in the process of Total Resilience. It also shows the human like a center of actions that ensure the continuity of the system, main element at Resilience (Anthropocentric View).     

Proper manual handling techniques to prevent low back pain, a Cochrane systematic review

Training and provision of assistive devices are considered major interventions to prevent and treat low back pain (LBP) among workers exposed to manual material handling (MMH). To establish the effectiveness of training and provision of assistive devices in preventing and treating LBP an update of a Cochrane literature review was performed to November 2010. Randomised controlled trials (RCTs) and cohort studies with a concurrent control group (CCTs) were included. Nine RCTs (20.101 employees) and nine CCTs (1280 employees) were included for prevention: six more than in the previous version. No study on treatment was found. None of the included RCTs and CCTs provided evidence that training and provision of assistive devices prevented LBP when compared to no intervention or another intervention.     

Designing for multiple global user populations: increasing resource allocation efficiency for greater sustainability

This paper proposes a method to identify opportunities for increasing the efficiency of raw material allocation decisions for products that are simultaneously targeted at multiple user populations around the world. The values of 24 body measures at certain key percentiles were used to estimate the best-fitting anthropometric distributions for female and male adults in nine national populations, which were selected to represent the diverse target markets multinational companies must design for. These distributions were then used to synthesize body measure data for combined populations with a 1:1 female:male ratio. An anthropometric range metric (ARM) was proposed for assessing the variation of these body measures across the populations. At any percentile, ARM values were calculated as the percentage difference between the highest and lowest anthropometric values across the considered user populations. Based on their magnitudes, plots of ARM values computed between the 1st and 99 th percentiles for each body measure were grouped into low, medium, and high categories. This classification of body measures was proposed as a means of selecting the most suitable strategies for designing raw material-efficient products. The findings in this study and the contributions of subsequent work along these lines are expected to help achieve greater efficiencies in resource allocation in global product development.     

Interventions to prevent needle stick injuries among health care workers

Needle stick injuries (NSIs) are frequently reported as occupational injuries among health care workers. The health effects of a NSI can be significant when blood-to-blood contact occurs from patient to health care worker. The objective of this study was to evaluate whether the number of NSIs decreased among health care workers at risk in one Dutch academic hospital after introduction of injection needles with safety devices in combination with an interactive workshop. In a cluster three-armed randomized controlled trial, 23 hospital divisions (n=796 health care workers) were randomly assigned to a group that was subjected to the use of a 'safety device plus workshop', to a group that was subjected to a 'workshop only' or to a control group with no intervention. The combined intervention of the introduction of needle safety devices and an interactive workshop led to the highest reduction in the number of self-reported NSIs compared to a workshop alone or no intervention. For practice, the use of relatively simple protective needle safety devices and interactive communication are effective measures for reducing NSI's.     

Burnout syndrome, working conditions, and health: a reality among public high school teachers in Brazil

The objective of the study was to evaluate the occurrence of Burnout Syndrome in 100 teachers of six public high schools and its correlation with working conditions in a southeast city of Brazil. Characterization of the sample occurred after application of a socio-demographic questionnaire. Evaluation of the working conditions was done by means of an Ergonomic Working Analysis. The presence of Burnout Syndrome was evaluated by means of the Maslach Burnout Inventory. The sample presented the predominance of women, with an average age of 40.4 and the majority married with children. Roughly 50% had less than 10 years of service, and more than half of the teachers taught more than 18 classes per week. Hoarseness after work was principally reported among women, which required many days off for health treatment. Environmental conditions reflect inadequacy in relation to noise, light, humidity and temperature. Presence of pain in the upper limbs was especially high among women. Risk of musculoskeletal disorders in the upper limbs predominated as moderately important to significant. We also identified an average distance walked by teachers of 1.5 Km and an average of 4.2 Kg of school supplies carried between classes. The Burnout Syndrome presented a high score for depersonalization principally among men, but it has association with both sexes. Emotional exhaustion correlates with noise, depersonalization, and personal fulfillment, in addition to the high number of weekly lessons. It can be concluded that Burnout syndrome is present among teachers, principally in terms of depersonalization, deserving the attention of government officials and the schools, as well as the teachers themselves.     

Designing dynamic distributed cooperative Human-Machine Systems

The paper presents a new approach to the development of cooperative human-machine systems in the Transportation domain which is currently researched in the European project D3CoS. A necessary precondition for the acceptance of cooperative human-machine systems with shared control is the confidence and trust of the user into the system. D3CoS tackles this important issue by addressing the cooperative system as the object and the target of the system development process. This new perspective, along with corresponding innovative methods, techniques and tools, shall allow the identification of optimal task and authority sharing approaches supported by intuitive human-machine interaction and user interfaces at an early stage of system development. This will support powerful teamwork between humans and machines or between machines and machines that is transparent, intuitive and easy to understand. The paper describes the research dimensions for the development of the methods, techniques and tools as well as first results.     

Activity analysis: contributions to the innovation of projects for aircrafts cabins

This article presents results obtained from some ergonomics intervention in the project for the conception of aircraft's cabins. The study's aim is to analyze the contribution of the method adopted in the passengers' activities analysis in reference situations, real-use situations in aircraft's cabins, applied to analyze typical activities performed by people in their own environment. Within this perspective, the study shows two analyses which highlight the use of electronic device. The first analysis has been registered through a shooting filming in a real commercial flight. In the second one, the use is developed within the domestic environment. The same method has been applied in both contexts and it is based on activity analysis. Starting with the filming activity, postures and actions analysis, self-confrontation interviews, action course reconstruction and elaboration of postures envelopes. The results point out that the developed method might be applied to different contexts, evincing different ways of space occupation to meet human personal needs while performing an activity, which can help us with the anticipation of the users' needs, as well as indicate some innovation possibilities.     

Contributions from the activity analysis to the products development project: case study based on a project of innovation and comfort in aircraft's cabins

Comfort is an issue that has gained relevance within the aeronautical industry due to the necessity of manufacturers and airline companies of differentiating themselves in a market that has become more and more competitive each day. This study's aim is to analyze the comfort/discomfort of passengers, based on the analysis of the activities performed in the aircrafts' cabin during real flights, in order to create ergonomics requirements and a methodology of comfort analysis. The study has been performed during domestic commercial flights, and the adopted data collection techniques have been: the application of 219 questionnaires to passengers, 44 registrations of postures and actions through filmings and 12 semistructured interviews. The method has made possible the reconstruction of the user's action course in performing activities in real flight situations, and the calculation of the area occupied by the passenger during his or her actions. The integrated analysis of the results corroborates data from previous studies in which both the space made available to each passenger and the activity performed interfere in their perception of comfort. From this study it has been concluded that the method constitutes itself as an innovative tool within the process of aircrafts' cabins project enabling the calculation of the action space based on the reconstructed course.     

Rationality,fairness and the cost of distrust

An adapted version of “the trust game with revenge” is applied to a Swedish setting. Senders – the first-movers – can keep an endowment of SEK 30, or give fractions or all to an unknown receiver. Donations are multiplied by five before reaching receivers, who may, or may not, send back part or the entire received amount. Half of the receivers are given information that the sender has the opportunity to exact revenge, while the remaining are not given this information. Results differ from Fehr and Gächter (2000), in the sense that the share of endowments sent in the first stage is around two thirds, compared to less than one third in Fehr and Gächter. Furthermore, they find a very strong effect of punishment while we find almost no effect. An efficiency frontier is defined and results show that that only 25% of the outcomes reach this frontier due to lack of trust. If senders were confident that receivers would return at least 20% of the donated amount, it is optimal to donate the whole endowment. Only about one-fifth returned of the receivers returned less than this, so for the most part the lack of trust is unwarranted.