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With increasing number of wirelessly connected devices having limited energy resources, energy efficient solutions become more and more important. Many studies have addressed schemes where low-power wake-up receivers are used to improve energy efficiency in networks with low traffic intensity (per node) and demands on availability. One such scheme is the duty-cycled wake-up receiver medium access
In this paper, full-and sub-structure characteristic modes (CMs) are explored through the effect of coupling between the target and background structures. The eigenvalues and eigen-current distributions of the first few modes are compared for different coupling levels in the numerical example. Similarities and differences between the two types of CMs in specific conditions are revealed, paving the
This paper presents a broadside antenna with three ports operating at the same frequency. The TM030 and TM003 modes of a patch are excited by two coaxial cables to generate two orthogonal linear polarizations. The patch can be transformed into a slotted SIW cavity whose TE201 and TE102 modes are jointly excited by the third cable. A matching cavity and a matching patch are introduced to broaden th
While research on the design of heterogeneous concurrent systems has a long and rich history, a unified design methodology and tool support has not emerged so far, and thus the creation of such systems remains a difficult, time-consuming and error-prone process. The absence of principled support for system evaluation and optimization at high abstraction levels makes the quality of the resulting im
Abstract in UndeterminedSoftware deployment, including both clean installs and updates, is a crucial activity for all software vendors. It starts with a customer's order of a new release and incorporates all steps taken until the customer is satisfied with the deployed product. Using interviews as the main data collection method, we conducted a case study of four companies to discover their softwa
This paper presents the main features of the TURNUS co-exploration environment, an unified design space exploration framework suitable for heterogeneous parallel systems designed using an high level dataflow representation. The main functions of this tool are illustrated through the analysis of a video decoder implemented in the RVC-CAL dataflow language.
In ubiquitous computing, end-user composition allows users to combine multiple single-purpose devices into new, interesting constellations. In PalCom – a ubiquitous middleware – this is achieved without the need to write program code. In this paper we present a solution that in the same way allows users to create Graphical User Interfaces (GUIs) for such systems without coding. The approach is to
Reliable connectivity between vehicles is a requirement for efficient overtaking warning systems. We investigate the 6 GHz propagation channel between oncoming vehicles with five different types of large obstructing vehicles in a poor scattering environment. The presented channel gains emphasize the advantages of different antenna positions and the difference between a straight road and curved roa
Algorithms for secure encryption in a post-quantum world are currently receiving a lot of attention in the research community, including several larger projects and a standardization effort from NIST. One of the most promising algorithms is the code-based scheme called QC-MDPC, which has excellent performance and a small public key size. In this work we present a very efficient key recovery attack
This work presents an analysis of the physical properties of sub-micrometer aerosol particles measured at the high Arctic site Villum Research Station, Station Nord (VRS), northeast Greenland, between July 2010 and February 2013. The study focuses on particle number concentrations, particle number size distributions and the occurrence of new particle formation (NPF) events and their seasonality in
One of the basic aspects of Massive MIMO (MaMi) that is in the focus of current investigations is its potential of using low-cost and energy-efficient hardware. It is often claimed that MaMi will allow for using analog-to-digital converters(ADCs) with very low resolutions and that this will result in overall improvement of energy efficiency. In this contribution, we perform a parametric energy eff
Multi-atlas segmentation has become a frequently used tool for medical image segmentation due to its outstanding performance. A computational bottleneck is that all atlas images need to be registered to a new target image. In this paper, we propose an intermediate representation of the whole atlas set – an überatlas – that can be used to speed up the registration process. The representation consis
Two different solutions for the characteristic modes (CMs) of lossy structures were previously developed using induced volume currents. The first solution diagonalizes the scattering and perturbation matrices, guaranteeing far-field orthogonality at the cost of imaginary eigenvalues and eigencurrents. The second solution does not perfectly diagonalize these matrices, but maintains real-valued eige
High computational cost is the main obstacle to adapting globally optimal branch-and-bound algorithms to intensity-based registration. Existing techniques to speed up such algorithms use a multiresolution pyramid of images and bounds on the target function among different resolutions for rigidly aligning two images. In this paper, we propose a dual algorithm in which the optimization is done in th
The ignition of nitromethane/O2/N2 mixtures was investigated via shock tube experiments in the temperature range 947–1333 K at reflected shock pressures near 8, 16 and 32 atm. The ignition was recorded as the intensity maxima of unfiltered luminosity in the range 240–530 nm. Under the experimental conditions of the present study, ignition was found to proceed via a two stage process. Dependencies
A Keyless Signing Infrastructure (KSI) provides users with a means to timestamp documents on a per-second basis. The KSI consists of a global infrastructure with several server layers and by using Merkle hash trees, the root hash can be used to verify the integrity and timestamp of a document. Regular publication of root hashes, e.g., once per month, allows a document to be verified without suppor
