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Augmented Reality (AR) has emerged as a technology able to greatly support the interaction between people and digital information by merging virtual objects with the real environment. So far, research in this field has been mainly focused on single-user scenarios with pre-stored digital data whose visualization needs to be appropriately and promptly aligned with physical objects. Instead, latest d

Given a set of commodities and a network where some arcs can fail while others are reliable, we first consider the problem of computing a minimum-cost pair of paths not sharing failing links. If a reliable link belongs to both paths then its cost is counted only once. We show that this problem can be solved in strongly polynomial time. Second, we consider a routing problem where each commodity can

We propose a depth cache that keeps the depth data in compressed format, when possible. Compared to previous work, this requires a more flexible cache implementation, where a tile may occupy a variable number of cache lines depending on whether it can be compressed or not. The advantage of this is that the effective cache size increases proportionally to the compression ratio. We show that the dep

In this technical report, we consider ultra light-weight constructions of message authentication in hardware applications. We examine several known constructions and evaluate details around their hardware implementations. These constructions are all based on the framework of universal hash functions.

This paper presents a method based on the phase dierence of arrival and the non-linear least square estimation to lo- calize a radio-frequency (RF) source, e.g a wireless capsule endoscope, inside the human body. The phase dierence of arrival at multiple frequencies of a signal is used to estimate the distance of the source to a receiver. The linear least square estimation is used to estimate the

The paper investigates advantages of using an MCCA-aware acknowledging system in IEEE 802.11s Wireless Mesh Networks (WMN). The MCCA (MCF controlled channel access) protocol allows for reserving time slots for a point-topoint transmission over a wireless link. The protocol assures that the transmission will not be hindered by any other 802.11 device that uses MCCA, by preventing all neighbors of b

This paper treats the feasibility to use only the sign bit of the in-phase and quadrature components when estimating time and frequency in OFDM systems. Using only the sign bit is shown to result in a frequency dependent bias, which can be easily compensated. The approach is evaluated for LTE and DVB-H, where the estimation is performed using the cyclic prefix, and for WLAN 802.11g, where the estim

We propose new M-algorithm BCJR (M-BCJR) algorithms for low-complexity turbo equalization and apply them to severe intersymbol interference (ISI) introduced by faster than Nyquist signaling. These reduced-search detectors are evaluated in simple detection over the ISI channel and in iterative decoding of coded FTN transmissions. In the second case, accurate log likelihood ratios are essential and

This paper discusses compact node-link formulations for MPLS fast reroute optimal single path layout. We propose mathematical formulations for MPLS fast reroute local protection mechanisms. In fact, we compare one-to-one (also called detour) local protection and many-to-one (also called facility backup) local protection mechanisms with respect to minimized maximum link utilization. The optimal res

Project retrospectives can be powerful tools for project teams to collectively identify communication gaps and practices to improve for future projects. However, even if project members take the time for a retrospective, it can be hard to correctly remember and jointly discuss past events in a constructive way. Fact-based timelines that visualize a project's events offer a possible solution.

Efficient and realistic mm-wave channel models are of vital importance for the development of novel mm-wave wireless technologies. Though many of the current 60 GHz channel models are based on the useful concept of multi-path clusters, only a limited number of 60 GHz channel measurements have been reported in the literature for this purpose. Therefore, there is still a need for further measurement

Optimal data detection of a linear channel can always be implemented through the Viterbi algorithm (VA). However, in many cases of interest the memory of the channel prohibits application of the VA. A popular and conceptually simple method in this case, studied since the early 70s, is to first filter the received signal in order to shorten the memory of the channel, and then to apply a VA that ope

The ignition delay is an important quantity in low temperature combustion concepts where a prolonged ignition delay gives an enhanced fuel-air mixing process, favorable for decreased particulate and NOx emission levels. This article investigates three different low-order physics-based correlation models and their ability to predict the ignition delay for the purpose of model-based controller desig

The aim of this thesis is to make it simple and efficient to produce applications for smartphones. The main area of application is within the health care sector, where alarm receiving devices are needed to inform personnel of pending situations. Most medical alarm systems are unique and hence require a unique GUI (Graphical User Interface). However, at the core, the main functionality is to commun

We consider the problem of migrating keys from TPM 1.2 to the backwardsincompatible TPM 2.0. The major differences betweenthe two versions introduce several challenges for deployed systems whensupport for TPM 2.0 is introduced. We show how TPM 2.0 support can beintroduced while still maintaining the functionality specified by TPM 1.2,allowing a smoother transition to the newer version. Specificall

Abstract:This doctoral thesis is addresses two topics in integrated circuit design: multiband direct conversion cellular receivers for cellular frequencies and beam steering transmitters for millimeter wave communication for the cellular backhaul. The trend towards cellular terminals supporting ever more different frequency bands has resulted in complex radio frontends with a large number of RF in

The computation power we expect from the various smart devices we use keeps increasing. Not only do we want faster devices but also less power hungry and energy efficient devices, both for the environment and our personal convenience (remember that "mobile phone" attached to a power plug at all times?).One way of addressing this demand is to build custom processor architectures that focus on a spe

MapReduce has become the standard model for supporting big data analytics. In particular, MapReduce job optimization has been widely considered to be crucial in the implementations of big data analytics. However, there is still a lack of guidelines especially for practitioners to understand how the MapReduce jobs can be optimized. This paper aims to systematic identify and taxonomically classify t