Sökresultat

In many application domains, critical systems must comply with safety standards. This involves gathering safety evidence in the form of artefacts such as safety analyses, system specifications, and testing results. These artefacts can evolve during a system's lifecycle, creating a need for impact analysis to guarantee that system safety and compliance are not jeopardised. Although extensive resear

Definition and reuse of robot instructions is still an art that requires extensive engineering, not only of the infrastructure but also of the adaptation of robot capabilities to the context and domain at hand. Technical approaches are numerous, but the lack of practical success is an indication of hidden difficulties, which we have experienced as complications over the last two decades. Based on

We derive the interarrival distribution of a workload input process which is a variation of the infinite source Poisson process for packet traffic. It accounts for long-range dependence and self-similarity exhibited by real traces in the Internet. The packet generation process is compound Poisson over each session which has a heavy tailed distribution. Considering the dependence induced by the wor

Forests and forestry are relevant for multiple uses and benefits. The increasing urgency of climate change warrants consideration of how to balance use of forests as a carbon sink and use of wood for products. Carbon sink benefits are recognized in climate science, international climate policy, and also integrated into, e.g. the EU’s climate mitigation pathways. Climate benefits of forest products

Programming languages are ever evolving, with new languages being invented to solve new problems, and old languages being extended to solve old problems in new ways. With the continued evolution of programming languages, and with new and improved static program analyses, we need flexible systems for building our static analyses and compilers. Declarative programming with Reference Attribute Gramma

Knowing whether a software feature will be completed in its planned iteration can help with release planning decisions. However, existing research has focused on predictions of only low-level software tasks, like bug fixes. In this paper, we describe a mixed-method empirical study on three large IBM projects. We investigated the types of iteration changes that occur. We show that up to 54% of high

Datalog has emerged as a powerful tool for expressing staticprogram analyses. Program analysis researchers have builtnontrivial code bases in Datalog, but tool support for workingwith Datalog itself has been lacking. In this paper, weintroduce MetaDL, a language extension to Datalog thatenables source-level Datalog program analysis within Datalog.We describe several program analyses implemented in

In the era of the Internet of Things and social media; communities, governments, and corporations are increasingly eager to exploit new technological innovations in order to track and keep up to date with important new events. Examples of such events include the news, health related incidents, and other major occurrences such as earthquakes and landslides. This area of research commonly referred t

We consider channel estimation (CE) in narrowband Internet-of-Things (NB-IoT) systems. Due to the fluctuations in phase within receiver and transmitter oscillators, and also the residual frequency offset (FO) caused by discontinuous receiving of repetition coded transmit data-blocks, random phase noises are presented in received signals. Although the coherent-time of fading channel can be assumed

Channel measurements of large-scale multiuser multiple-input multiple-output (MU-MIMO) radio propagation channels are presented. In the setup, three users with patch antennas communicate simultaneously with a base station (BS) equipped with a large antenna array in an indoor environment. Both a uniform linear array (ULA) and a uniform planar array (UPA) are used, and their relative ability to sepa

Massive multiple-input multiple-output (MIMO) arrays are becoming critical elements in cellular base station infrastructure. We utilize the theory of characteristic modes (TCM) to design a novel tri-modal broadside antenna element which is suitable for the construction of compact massive MIMOarrays. The proposed antenna element consists of three ports which is formed by reviewing an existing compa

We analyze the downlink of a massive multiuser multiple input, multiple output (MIMO) system where antenna units at the base station are connected in a daisy chain without a central processing unit and only possess local channel knowledge. For this setup, we develop and analyze a linear precoding algorithm for suppressing interuser interference. It is demonstrated that the algorithm is close to ze

Reliable wireless communication links are a critical but challenging aspect for high-speed railway (HSR). To develop and analyze such systems, accurate models for the propagation channel are required. The radio channel properties in HSR scenarios are different from those in cellular scenarios not only due to the high velocity, but also due to the special construction elements and the type of surro

This paper presents a 16-lane, 16-bit complex application-specific instruction processor (ASIP) for baseband processing in massive multiple-input multiple-output (MIMO). The architecture utilizes a 3/4-way very large instruction word (VLIW) with highly efficient pre- and post-processing units specifically trimmed for massive MIMO requirements. Architecture optimizations include features like singl

This summary refers to the paper 'Comparison of the FMEA and STPA safety analysis methods-a case study' [Su17]. The paper was published as an article in the Software Quality Journal. It compares the Failure Mode and Effect Analysis (FMEA) and the System Theoretic Process Analysis (STPA) in an industrial case study.