In Attention Deficit Hyperactivity Disorder (AD(H)D), treatments using methylphenidate (MPH) and behavioralinterventions like neurofeedback (NF) reflect major therapeutic options. These treatments also ameliorate ex-ecutive dysfunctions in AD(H)D. However, the mechanisms underlying effects of MPH and NF on executivefunctions in AD(H)D (e.g. the ability to inhibit prepotent responses) are far from understood. It is particularlyunclear whether these interventions affect similar or dissociable neural mechanisms and associated functionalneuroanatomical structures. This, however, is important when aiming to further improve these treatments. Wecompared the neurophysiological mechanisms of MPH and theta/beta NF treatments on inhibitory control on the basis of EEG recordings and source localization analyses. The data show that MPH and theta/beta NF bothincrease the ability to inhibit pre-potent responses to a similar extent. However, the data suggest that MPH andNF target different neurophysiological mechanisms, especially when it comes to functional neuroanatomicalstructures associated with these effects. Both treatments seem to affect neurophysiological correlates of a‘braking function’ in medial frontal areas. However, in case of the NF intervention, inferior parietal areas are alsoinvolved. This likely reflects the updating and stabilisation of efficient internal representations in order to in-itiate appropriate actions. No effects were seen in correlates of perceptual and attentional selection processes.Notably, reliable effects were only obtained after accounting for intra-individual variability in the neurophy-siological data, which may also explain the diversity of findings in studies on treatment effects in AD(H)D,especially concerning neurofeedback.

Networks with hundreds of ad hoc nodes equipped with communication and position finding abilities are conceivable with recent advancements in technology. Methods are presented in this thesis to assess the communicative capabilities and node position estimation of mobile ad hoc networks. Specifically, we investigate techniques for providing communication and geolocation with specific characteristics in wireless ad hoc networks. The material presented in this thesis, communication and geolocation, may initially seem a collection of disconnected topics related only distantly under the banner of ad hoc networks. However, systems currently in development combining these techniques into single integrated systems. In this thesis first, we investigate the effect of multilayer interaction, including fading and path loss, on ad hoc routing protocol performance, and present a procedure for deploying an ad hoc network based on extensive simulations. Our first goal is to test the routing protocols with parameters that can be used to characterize the environment in which they might be deployed. Second, we analyze the location discovery problem in ad hoc networks and propose a fully distributed, infrastructure-free positioning algorithm that does not rely on the Global Positioning System (GPS). The algorithm uses the approximate distances between the nodes to build a relative coordinate system in which the node positions are computed in three-dimensions. However, in reconstructing three-dimensional positions from approximate distances, we need to consider error threshold, graph connectivity, and graph rigidity. We also statistically evaluate the location discovery procedure with respect to a number of parameters, such as error propagation and the relative positions of the nodes.