Testing Multiple Coordination Constraints with a Novel Bimanual Visuomotor Task

The acquisition of a new bimanual skill depends on several motor coordination constraints. To date, coordination constraints have often been tested relatively independently of one another, particularly with respect to isofrequency and multifrequency rhythms. Here, we used a new paradigm to test the interaction of multiple coordination constraints. Coordination constraints that were tested included temporal complexity, directionality, muscle grouping, and hand dominance. Twenty-two healthy young adults performed a bimanual dial rotation task that required left and right hand coordination to track a moving target on a computer monitor. Two groups were compared, either with or without four days of practice with augmented visual feedback. Four directional patterns were tested such that both hands moved either rightward (clockwise), leftward (counterclockwise), inward or outward relative to each other. Seven frequency ratios (3∶1, 2∶1, 3∶2, 1∶1, 2∶3. 1∶2, 1∶3) between the left and right hand were introduced. As expected, isofrequency patterns (1∶1) were performed more successfully than multifrequency patterns (non 1∶1). In addition, performance was more accurate when participants were required to move faster with the dominant right hand (1∶3, 1∶2 and 2∶3) than with the non-dominant left hand (3∶1, 2∶1, 3∶2). Interestingly, performance deteriorated as the relative angular velocity between the two hands increased, regardless of whether the required frequency ratio was an integer or non-integer. This contrasted with previous finger tapping research where the integer ratios generally led to less error than the non-integer ratios. We suggest that this is due to the different movement topologies that are required of each paradigm. Overall, we found that this visuomotor task was useful for testing the interaction of multiple coordination constraints as well as the release from these constraints with practice in the presence of augmented visual feedback

Exploration of the ethical dimension of Network Enabled Operations : toward a philosophical framework of analysis

The transformation to Network Enabled Operations (NEO) is based on a vision of intensive military cooperation and information sharing by making use of network technologies. Underlying this vision are moral assumptions on how people will behave when operating in a network. The current status of NEO research leaves out the ethical dimension of working in a highly technologically mediated environment. Also research on military ethics does not take into account the way technology possibly affects moral behaviour. Therefore there is a need to develop a philosophical framework to analyse NEO. Philosophy of technology serves as a background to study the role of technology when making moral decisions. A framework developed by Herman Dooyeweerd called ‘multi aspects’ analysis is used to explore the coherence, unity and diversity in which NEO functions in practice. An analysis of NEO in terms of the 15 aspects is presented. Implications from this analysis for empirical research to study specific problems and ethical issues in NEO are discussed

Exploration of the ethical dimension of Network Enabled Operations : toward a philosophical framework of analysis

The transformation to Network Enabled Operations (NEO) is based on a vision of intensive military cooperation and information sharing by making use of network technologies. Underlying this vision are moral assumptions on how people will behave when operating in a network. The current status of NEO research leaves out the ethical dimension of working in a highly technologically mediated environment. Also research on military ethics does not take into account the way technology possibly affects moral behaviour. Therefore there is a need to develop a philosophical framework to analyse NEO. Philosophy of technology serves as a background to study the role of technology when making moral decisions. A framework developed by Herman Dooyeweerd called ‘multi aspects’ analysis is used to explore the coherence, unity and diversity in which NEO functions in practice. An analysis of NEO in terms of the 15 aspects is presented. Implications from this analysis for empirical research to study specific problems and ethical issues in NEO are discussed

De productie van 1,4 butaandiol uit 1,3 butadieen

Document uit de collectie Chemische ProcestechnologieDelftChemTechApplied Science

Measuring Effectiveness of Teams and Multi-team Systems in Operation

Military operations have evidently become more complex. The development toward multi-service, multi-national operations with teams often functioning in larger systems of teams is one of the complexities commanders have to deal with. Therefore commanders need not only to gain and maintain insight in the effectiveness of single teams but also in the performance of the multi-team system as a whole. The Command Team Effectiveness instrument is a diagnostic instrument for commanders to assess within team aspects, processes and effectiveness (Essens et al., 2005). We extended this instrument to include a module on multi-team system characteristics and cross team processes. Furthermore, we developed a simple support system for easy data collection, processing data, and reporting to improve the usability of the instrument in the operational context. The support system is currently being used in a Naval-Marines mission (Atalanta, 2009). We will discuss the strengths and limitations of using the support system for measurement of staff processes during operational missions

The Bayesian way to relate rhythm perception and production

Contains fulltext : 55443.pdf (publisher's version ) (Open Access)Measurement of the perception and production of simple rhythmic patterns have been shown not to be in line in some cases. In this study it is demonstrated that a Bayesian approach provides a new way of understanding this difference, by formalizing the perceptual competition between mental representations and assuming possible nonuniform a priori probabilities of the rhythmic categories. Thus we can relate the two kinds of information and predict perception data from production data. In this approach, the contrast between rhythm perception and production data, taken from different studies in the literature, was shown almost to disappear, assembling independent prior probabilities from counts of patterns in corpora of musical scores, or from a theoretical measure of rhythmic complexity. The success of this Bayesian formalization may be interpreted as an optimal adaptation of our perceptual system to the environment in which the produced rhythms occur.10 p