Filetype
We study network SIR (Susceptible - Infected - Recovered) epidemic models in the case of two interacting populations. We analyze the dynamics behavior of the fractions of infected individuals in the two populations. In contrast to the classical scalar SIR epidemic model, where the fraction of infected individuals is known to have an unimodal behavior (either decreasing throughout time or initially
Social influence is largely recognized as a key factor in opinion formation processes. Recently, the role of external forces in inducing opinion displacement and polarization in social networks has attracted significant attention. This is in particular motivated by the necessity to understand and possibly prevent interference phenomena during political campaigns and elections. In this paper, we fo
We present a new, scalable alternative to the structured singular value, which we call v, provide a convex upper bound, study their properties and compare them to l1 robust control. The analysis relies on a novel result on the relationship between robust control of dynamical systems and non-negative constant matrices.
Carefully selecting the right collection datastructure can significantly improve the performance of a Java program. Unfortunately, the performance impact of a certain collection selection can be hard to estimate.To assist developers there are tools that recommend collections to use based on static and/or dynamic information about a program. The majority of existing collection selection tools for J
Statistics are part of any empirical science, and performance analysis is no exception. However, for non-statisticians, picking the right statistical tool to answer a research question can be challenging; each statistical tool comes with a set of assumptions, and it is not clear to researchers what happens when those assumptions are violated. Bayesian statistics offers a framework with more flexib
Human activities in coastal areas have intensified over the last 200 years, impacting also high-latitude regions such as the Baltic Sea. Benthic foraminifera, protists often with calcite shells (tests), are typically well preserved in marine sediments and known to record past bottom-water conditions. Morphological analyses of marine shells acquired by microcomputed tomography (µCT) have made signi
This article presents a fully integrated millimeter-wave (mmW) transceiver front end covering 24.25–29.5 GHz. It features a wideband Doherty power amplifier utilizing adaptive bias and a transmit/receive switch (TRX-switch) that has embedded low noise amplifier to antenna matching. The phase shift of 90
Multi-sample anti-aliasing is a popular technique for reducing geometric aliasing (jagged edges) and is supported in all modern graphics processors. With multi-sampling anti-aliasing, visibility and depth are sampled more than once per pixel, while shading is done only once per pixel per primitive. Although this significantly reduces the appearance of jagged edges around object boundaries, the ima
We present a new SAH guided approach to subdividing triangles as the scene is coarsely partitioned into smaller sets of spatiallycoherent triangles. Our triangle split approach is integrated into the partitioning stage of a fast BVH construction algorithm, butmay as well be used as a stand alone pre-split pass. Our algorithm significantly reduces the number of split triangles comparedto previous m
This paper reports on a case study in which an at- size application is ported onto a commercially available processor array. Its purpose is threefold: (1) Determine the suitability of processor arrays for this kind of application. (2) Develop a runtime software infrastructure that supports streaming applications on processor arrays. (3) Gather data and insights into the resulting system performanc
With the arrival of heterogeneous manycores comprising various features to support task, data and instruction-level parallelism, developing applications that take full advantage of the hardware parallel features has become a major challenge. In this paper, we present an extension to our CAL compilation framework (CAL2Many) that supports data parallelism in the CAL Actor Language. Our compilation f
The problem of joint source-channel coding is considered for a stationary remote (noisy) Gaussian source and a Gaussian channel. The encoder and decoder are assumed to be causal and their combined operations are subject to a delay constraint. It is shown that, under the mean-square error distortion metric, an optimal encoder-decoder pair from the linear and time-invariant (LTI) class can be found
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
We present a novel architecture for flexible control of shading rates in a GPU pipeline, and demonstrate substantially reduced shading costs for various applications. We decouple shading and visibility by restricting and quantizing shading rates to a finite set of screen-aligned grids, leading to simpler and fewer changes to the GPU pipeline compared to alternative approaches. Our architecture int
Developers need to comprehend new code on a regular basis; a demanding task that gets complicated as projects grow in complexity and size. To help developers, documentation is typically added in the form of code comments, design documents, system documents, to name a few examples. Despite all these different kinds of documentation code base comprehension is still challenging and there is room for
The improvements in GPU hardware, including hardware-accelerated ray tracing, and the push for fully dynamic realistic-looking video games, has been driving more research in the use of ray tracing in real-time applications. The work described in this thesis covers multiple aspects such as optimisations, adapting existing offline methods to real-time constraints, and adding effects which were hard
