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With the growing popularity of audio and video communication services on the Internet, network operators, service providers and application developers are becoming increasingly interested in assuring that their services give the best possible experience to the users. Since real-time audio and video services are very sensitive to packet loss, latency and bandwidth variations, the performance of the

Using multiple receivers (microphones or antennas) in a rigid configuration, such as on a smartphone, it is possible to measure time difference of arrival to the receivers. This in turn can be used to determine the direction to the transmissions, if there are at least three receivers. When using two receivers it can be used to determine the angle to the transmissions relative to the line through t

This paper considers switching output feedback control of linear systems and variable structure systems. Theory for stability analysis and design for a class of observer-based feedback control systems is presented. A circle-criterion approach can be used to design an observer-based state feedback control which yields a closed-loop system with specified robustness characteristics. The approach is r

Consider the communication model (y) over bar = H F (x) over bar + (n) over bar, where H; F are real-valued matrices, (x) over bar is a data vector drawn from some real-valued lattice (e.g. M-PAM), (n) over bar is additive white Gaussian noise and (y) over bar is the received vector. It is assumed that the transmitter and the receiver have perfect knowledge of the channel matrix H (perfect CSI) an

Shadowing from other vehicles can degrade the performance of vehicle-to-vehicle communication systems significantly. It is thus important to characterize and model the influence of common shadowing objects like trucks in a proper way. However, the scenario of a truck as an obstacle in highly dynamic rural and highway environments is not yet well understood. In this paper we analyze the distance de

We consider demand response solutions having the capability to monitor different variables at users' premises, like presence and temperature, and to control individual appliances. We focus on the optimal control of the appliances during time periods where the available capacity is not enough to satisfy the demand generated by houses operating freely. We propose an approach to define the utility of

From its early days, the academic debate on public goods has focused on discrepancies or trade-offs regarding the provision of public goods on the one hand and private goods on the other. However, both the extension of the public domain and an increasing interdependence in international relations clearly drive the expansion of an agenda in which there are a growing number of cases where public goo

Spatially-Coupled LDPC (SC-LDPC) codes have been recently shown to be very efficient for transmissions over nonergodic channels, in particular over block-fading channels [1]. In fact, it is possible to design a SC-LDPC code with any given code diversity [2]. In this work, we investigate the performance of SC-LDPC codes over block-fading channels, assuming a mismatch (or offset) between the first b

We introduce a mixed-integer optimization model for two-layer IP-over-Flexgrid networks, and present a cost study performed using the CPLEX package for the introduced model. The study concerns a generic German network with 12 nodes and 20 links in the optical layer, and a set of six IP traffic matrices with increasing demand volumes. The optimization assumes a hot-standby mechanism in the optical

In industry–academia collaboration projects, there are many issues related to different time horizons in industry and academia. If not adressed upfront, they may hinder collaboration in such projects. We analyze our experiences from a 10 year industry–academia collaboration program, the EASE Industrial Excellence Center in Sweden, and identify issues and feasible practices to overcome the hurdles

The use of large-scale antenna arrays can bring substantial improvements both in energy and spectral efficiency. This paper presents an initial study of user equipment (UE) antenna performance based on prototypes for a massive MIMO test bed. Most publications in the massive MIMO area have assumed isotropic or dipole antenna behavior at the UE side. It is, however, of greatest interest to evaluate

Popular AbstractAvhandlingen presenterar, från ett fenomenologiskt perspektiv, interaktionen mellan naturvetenskapens kunskap och annan kunskap, här kallad "vardagskunskap". Utgångspunkten i presentationen är människans existens. Två aspekter av denna lyfts fram som centrala - att människan är kroppsligt utsatt för, berörd av, något hon inte har full kontroll över, samt att hon alltid agerar utifrThe dissertation presents a phenomenological view on the interaction between science knowledge and prescientific knowledge. Drawing on Husserl, Merleau-Ponty and Lévinas the human bodily grounded existence is described, the central feature of this existence being its responsivity to the Other. This responsivity is presented as the starting point for the production of science knowledge, thus making

Christian Zionism is usually characterized as a theological and political movement grounded in literalist bible hermeneutics and End-time speculations that dedicate unwavering support to the State of Israel and the Jewish people. The prophetic element in Christian Zionism has in later years been downplayed for a more down-to-earth focus on social and political commitment to the well-being of the s

There has been extensive research about single link multiple-input multiple-output (MIMO) channels, both simulated and measured, but only few studies have targeted multilink analysis with measured channel data. Hence, in this paper, we analyze the influence of spatial separation of user terminals and the human shadowing effect on the MIMO capacity and to the signal to interference ratio (SIR) in a