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Objective: We studied the relation between dynamic (isokinetic) strength and the batch-assorting strategy to initiate a manual materials-handling task and the effect of knowledge of strength on that relation. Background: The debated, complex relationship between muscular strength and the risk of injury can be better understood from a behavioral perspective by examining performance strategies in physical acts such as lifting. Methods: Thirty-two participants (16 men and 16 women) were first tested for their isokinetic strengths of trunk extension, knee extension, shoulder extension, and shoulder abduction. The participants were then divided into two groups, one provided with knowledge feedback of their strength testing results and the other not provided with such feedback. Participants subsequently performed the same load-handling task in which they carried batches of various weight plates while allowed to assort batches of more than one plate into any combination. Results: Dynamic strength, as represented by a total isokinetic strength score, and knowledge feedback both had significant effects on measures quantifying the batch-assorting strategy. Conclusion: Individuals with greater strength tended to adopt a strategy corresponding to a heavier load per carry and fewer carries per batch. Receiving knowledge feedback evoked a tendency toward handling a heavier load, and this tendency was more salient in the weaker individuals. Application: Potential applications include the use of strength testing in worker selection and training as well as in job design to promote better strategies of balancing productivity and injury prevention.

Throughout the European Union there is an increasing amount of wind generation being dispatched-down due to the binding of power system operating constraints from high levels of wind generation. This paper examines the impact a system non-synchronous penetration limit has on the dispatch-down of wind and quantifies the significance of interconnector counter-trading to the priority dispatching of wind power. A fully coupled economic dispatch and security constrained unit commitment model of the Single Electricity Market of the Republic of Ireland and Northern Ireland and the British Electricity Trading and Transmission Arrangement was used in this study. The key finding was interconnector counter-trading reduces the impact the system non-synchronous penetration limit has on the dispatch-down of wind. The capability to counter-trade on the interconnectors and an increase in system non-synchronous penetration limit from 50% to 55% reduces the dispatch-down of wind by 311 GW h and decreases total electricity payments to the consumer by €1.72/MW h. In terms of the European Union electricity market integration, the results show the importance of developing individual electricity markets that allow system operators to counter-trade on interconnectors to ensure the priority dispatch of the increasing levels of wind generation.

Electric vehicles (EVs) offer great potential to move from fossil fuel dependency in transport once some of the technical barriers related to battery reliability and grid integration are resolved. The European Union has set a target to achieve a 10% reduction in greenhouse gas emissions by 2020 relative to 2005 levels. This target is binding in all the European Union member states. If electric vehicle issues are overcome then the challenge is to use as much renewable energy as possible to achieve this target. In this paper, the impacts of electric vehicle charged in the all-Ireland single wholesale electricity market after the 2020 deadline passes is investigated using a power system dispatch model. For the purpose of this work it is assumed that a 10% electric vehicle target in the Republic of Ireland is not achieved, but instead 8% is reached by 2025 considering the slow market uptake of electric vehicles. Our experimental study shows that the increasing penetration of EVs could contribute to approach the target of the EU and Ireland government on emissions reduction, regardless of different charging scenarios. Furthermore, among various charging scenarios, the off-peak charging is the best approach, contributing 2.07% to the target of 10% reduction of Greenhouse gas emissions by 2025.