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MIMO technology has facilitated tremendous performance improvements in wireless communications, allowing the data rate to increase linearly with the number of antennas used, at no additional expense in transmit power or spectrum. However, the tremendous performance gain can only be achieved by multi-antenna designs that provide low coupling and correlation, as well as high total efficiency. Such d

Video content constitutes a large share of residential Internet traffic. The major source of video content as of today is YouTube. In this paper, we analyse the user demand patterns for YouTube in two metropolitan access networks with more than 1 million requests over three consecutive weeks in the first network and more than 600,000 requests over four consecutive weeks in the second network. In p

In this paper an approach for improving robot machining accuracy through simulation-assisted path planning within Computer-Aided Manufacturing (CAM) tools is investigated. The method comprises modeling of dynamic robot behaviour under influence of process forces and a subsequent simulation of the robot motion which results in an offline prediction of deflection errors during the machining task. Th

In this chapter a technology for the enhancement of video data obtained at low light levels is presented. The method was inspired by the way in which nocturnal animals adaptively sum intensities, spatially and temporally, to improve vision at night. Due to the low photon count under these conditions the visual input is dark and unreliable, which leads to noisy low contrast images. The noise become

This article describes results of the work on knowledge representation techniques chosen for use in the European project SIARAS (Skill-Based Inspection and Assembly for Reconfigurable Automation Systems). Its goal was to create intelligent support system for reconfiguration and adaptation of robot-based manufacturing cells. Declarative knowledge is represented first of all in an ontology expressed

Recently, the multiplexing efficiency metric is proposed for characterizing the MIMO performance of terminal antennas. Here, we show that it can also provide useful insights into the impact of user on MIMO terminal performance. In particular, the impact of user hand and head on the efficiency and correlation of a MIMO antenna can be conveniently quantified using the multiplexing efficiency metric.

Video-on-Demand (VoD) and video sharing services account for a large percentage of the total downstream Internet traffic. In order to provide a better understanding of the load on these services, we analyze and model a workload trace from a VoD service provided by a major Swedish TV broadcaster. The trace contains over half a million requests generated by more than 20000 unique users. Among other

The diversity of different life-forms, their conquest of virtually all available habitats, and their seemingly limitless ability to adapt to new ecological challenges show that structural and physiological specializations of a few basic building plans uniquely match plants and animals to the specific lives they lead.

This paper presents a receiver architecture for intraband dual-carrier reception as specified for the upcoming releases of 3GPP WCDMA and LTE standards. It is based on a time-discrete harmonic rejection complex-IF mixer to limit the bandwidth requirements on the ADCs to that of a single carrier. The mixer has been designed and fabricated together with a 3rd order continuous-time (CT) delta-sigma A

Reconstruction of movement control properties of the brain could result in many potential advantages for application in robotics. However, a hampering factor so far has been the lack of knowledge of the structure and function of brain circuitry in vivo during movement control. Much more detailed information has recently become available for the area of the cerebellum that controls arm–hand movemen

In this work, we study YouTube traffic characteristics in a medium-sized Swedish residential municipal network that has 2600 mainly FTTH broadband-connected households. YouTube traffic analyses were carried out in the perspective of video clip category and duration, in order to understand their impact on the potential local network caching gains. To the best of our knowledge, this is the first tim

In this paper, we confirm that angle and polarization diversities are indeed the dominant diversity mechanisms of a recently proposed compact six-port MIMO antenna array, as it exhibits similar effective degree-of-freedom (EDOF) performance as that of the ideal array with co-located antenna elements evaluated in propagation scenarios with different angular spreads. Furthermore, the same approach c

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Box jellyfish have an impressive set of 24 eyes of four different types, including eyes structurally similar to those of vertebrates and cephalopods [1, 2]. However, the known visual responses are restricted to simple phototaxis, shadow responses, and object avoidance responses [3-8], and it has been a puzzle why they need such a complex set of eyes. Here we report that medusae of the box jellyfis

Cellular-based localization and sensing pave the way for a variety ofapplications across various domains, ranging from autonomous driv-ing to emergency care and intelligent traffic management. Althoughtraditional methods have been effective, they still face challenges such as therequirement for highly accurate models and the inherent complexity of thealgorithms. This thesis explores the potential

Iterative algorithms are becoming more common in modern systems. This ranges from algorithms for communicationsystems receivers, machine learning, group testing, and various computation problems. The success of thesealgorithms lies in the ability to simplify computation by breaking down the system into components and exchangingmessages on graphs. The graph has the components as nodes and connectio

Maritime communication is one of the 5G vertical domains and is attracting more attention. Advanced channel models that accurately characterize the wideband maritime propagation channels are essential for the development of modern maritime communication technologies. To this end, we measured the propagation channel at 5.6GHz with a sailing boat, capturing the channel with a bandwidth of 250MHz, bo