940 research outputs found
FPGA Implementation of a Frame Synchronization Algorithm for Powerline Communications
This paper presents an FPGA implementation of a pilotâbased time synchronization scheme employing orthogonal frequency division multiplexing for powerline communication channels. The functionality of the algorithm is analyzed and tested over a real powerline residential network. For this purpose, an appropriate transmitter circuit, implemented by an FPGA, and suitable coupling circuits are constructed. The system has been developed using VHDL language on Nallatech XtremeDSP development kits. The communication system operates in the baseband up to 30 MHz. Measurements of the algorithm's good performance in terms of the number of detected frames and timing offset error are taken and compared to simulations of existing algorithms
Emission Permits and Public Pollution Abatement
We build a two regions general equilibrium model with cross-border pollution and either international or only inter-regional capital mobility. To control pollution each region uses public pollution abatement and issues either intra-regionally or inter-regionally tradable emission permits. We analyze the non-cooperative (decentralized) and cooperative (centralized) equilibrium level of emission permits and we examine when and how cross-border pollution and the type of capital mobility affect these equilibrium policies. We provide the welfare ranking of the policies in the various cases and we investigate under what conditions the decentralized and centralized equilibrium policies are equally efficient
On the Efficiency of Destination and Origin Commodity Taxation in the Presence of Consumption Generated Cross-Border Pollution
We combine consumption generated cross-border pollution and public pollution abatement in a theoretical framework to examine the efficiency of the destination and origin principles of commodity taxation. The key result of our study is that with public pollution abatement, the non-cooperative equilibrium origin-based consumption taxes are set efficiently. This result holds not only in the context of symmetric countries, but under certain conditions carry over also to asymmetric countries. The non-cooperative equilibrium destination-based consumption taxes are inefficient. In the absence of public pollution abatement, the Nash equilibrium commodity taxes under either taxation principle are inefficient
A Gamification Engine Architecture for Enhancing Behavioral Change Support Systems
This paper presents a gamified framework designed to offer behavioural change support and treatment adherence services to people living with Dementia (PLWD), their caregivers and medical/social professionals
Dynamics of Nanometer-Scale Foil Targets Irradiated with Relativistically Intense Laser Pulses
In this letter we report on an experimental study of high harmonic radiation
generated in nanometer-scale foil targets irradiated under normal incidence.
The experiments constitute the first unambiguous observation of odd-numbered
relativistic harmonics generated by the component of the
Lorentz force verifying a long predicted property of solid target harmonics.
Simultaneously the observed harmonic spectra allow in-situ extraction of the
target density in an experimental scenario which is of utmost interest for
applications such as ion acceleration by the radiation pressure of an
ultraintense laser.Comment: 5 pages, 4 figure
Measuring the effects through time of the influence of visuomotor and visuotactile synchronous stimulation on a virtual body ownership illusion
Previous studies have examined the experience of owning a virtual surrogate body or body part through specific combinations of cross-modal multisensory stimulation. Both visuomotor (VM) and visuotactile (VT) synchronous stimulation have been shown to be important for inducing a body ownership illusion, each tested separately or both in combination. In this study we compared the relative importance of these two cross-modal correlations, when both are provided in the same immersive virtual reality setup and the same experiment. We systematically manipulated VT and VM contingencies in order to assess their relative role and mutual interaction. Moreover, we present a new method for measuring the induced body ownership illusion through time, by recording reports of breaks in the illusion of ownership ("breaks") throughout the experimental phase. The balance of the evidence, from both questionnaires and analysis of the breaks, suggests that while VM synchronous stimulation contributes the greatest to the attainment of the illusion, a disruption of either (through asynchronous stimulation) contributes equally to the probability of a break in the illusion
Impact of loss of high-molecular-weight von Willebrand factor multimers on blood loss after aortic valve replacement
Background Severe aortic stenosis is associated with loss of the largest von Willebrand factor (vWF) multimers, which could affect primary haemostasis. We hypothesized that the altered multimer structure with the loss of the largest multimers increases postoperative bleeding in patients undergoing aortic valve replacement. Methods We prospectively included 60 subjects with severe aortic stenosis. Before and after aortic valve replacement, vWF antigen, activity, and multimer structure were determined and platelet function was measured by impedance aggregometry. Blood loss from mediastinal drainage and the use of blood and haemostatic products were evaluated perioperatively. Results Before operation, the altered multimer structure was present in 48 subjects (80%). Baseline characteristics and laboratory data were similar in all subjects. The median blood loss after 6 h was 250 (105-400) and 145 (85-240) ml in the groups with the altered and normal multimer structures, respectively (P=0.182). After 24 h, the cumulative loss was 495 (270-650) and 375 (310-600) ml in the groups with the altered and normal multimer structures, respectively (P=0.713). Multivariable analysis revealed no significant influence of multimer structure and platelet function on bleeding volumes after 6 and 24 h. After 24 h, there was no obvious difference in vWF antigen, activity, and multimer structure in subjects with and without the altered multimer structure before operation or in subjects with and without perioperative plasma transfusion. Conclusions The altered vWF multimer structure before operation was not associated with increased bleeding after aortic valve replacement. Our findings might be explained by perioperative release of vWF and rapid recovery of the largest vWF multimer
The self in the mindâs eye: revealing how we truly see ourselves through reverse correlation
Is there a way to visually depict, for all to see, how people "see" themselves with their mindsâ eyes? And if so, what can these mental images tell us about ourselves? We use a computational reverse-correlation technique to explore individualsâ mental âself-portraitsâ, of their faces and body shapes, in an unbiased, data-driven way (total N = 116). Self-portraits were similar to individualsâ real faces, but importantly, also contained âcluesâ to each personâs self-reported personality traits, which were reliably detected by external observers. Furthermore, people with higher social self-esteem produced more true-to-life self-portraits. Unlike face-portraits, body-portraits had negligible relationships with individualsâ actual body shape, but as with faces, they were influenced by peopleâs beliefs and emotions. We show how psychological beliefs and attitudes about oneself bias the perceptual representation of oneâs appearance, and provide a unique window into the internal mental self-representation, with important implications for mental health and visual culture
Self-Motion Holds a Special Status in Visual Processing
Agency plays an important role in self-recognition from motion. Here, we investigated whether our own movements benefit from preferential processing even when the task is unrelated to self-recognition, and does not involve agency judgments. Participants searched for a moving target defined by its known shape among moving distractors, while continuously moving the computer mouse with one hand. They thereby controlled the motion of one item, which was randomly either the target or any of the distractors, while the other items followed pre-recorded motion pathways. Performance was more accurate and less prone to degradation as set size increased when the target was the self-controlled item. An additional experiment confirmed that participant-controlled motion was not physically more salient than motion recorded offline. We found no evidence that self-controlled items captured attention. Taken together, these results suggest that visual events are perceived more accurately when they are the consequences of our actions, even when self-motion is task irrelevant
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