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The role of computer science and IT in Swedish schools has varied throughout the years. In fall 2014, the Swedish government gave the National Agency for Education (Skolverket) the task of preparing a proposal for K–9 education on how to better address the competences required in a digitalized society. In June 2016, Skolverket handed over a proposal introducing digital competence and programming a
Context: The increased use of Open Source Software (OSS) affects how software-intensive product development organizations (SIPDO) innovate and compete, moving them towards Open Innovation (OI). Specifically, software engineering tools have the potential for OI, but require better understanding regarding what to develop internally and what to acquire from outside the organization, and how to cooper
The first measured results for massive multiple-input, multiple-output (MIMO) performance in a line-of-sight (LOS) scenario with moderate mobility are presented, with 8 users served by a 100 antenna base Station (BS) at 3.7 GHz. When such a large number of channels dynamically change, the inherent propagation and processing delay has a critical relationship with the rate of change, as the use of o
This paper presents achievable uplink (UL) sum-rate predictions for a measured line-of-sight (LOS) massive multiple-input, multiple-output (MIMO) (MMIMO) scenario and illustrates the trade-off between spatial multiplexing performance and channel de-coherence rate for an increasing number of base station (BS) antennas. In addition, an orthogonal frequency division multiplexing (OFDM) case study is
This paper proposes a substrate integrated waveguide (SIW) slot antenna array for wideband gigabyte mobile radio application in E-band. The wideband unit cell design is based on simultaneous feeding of 4-element radiation slots with a higher order cavity mode directly excited by a simple slot aperture fed by a microstrip fork-like tuning stub. Employing the higher order mode along with the slot ap
We consider a multipair two-way relay communication network, where pairs of user devices exchange information via a relay system. The communication between users employs time division duplex, with all users transmitting simultaneously to relays in one time slot and relays sending the processed information to all users in the next time slot. The relay system consists of a large number of single ant
The communication of requirements within software development is vital for project success. Requirements engineering and testing are two processes that when aligned can enable the discovery of issues and misunderstandings earlier, rather than later, and avoid costly and time-consuming rework and delays. There are a number of practices that support requirements-test alignment. However, each organis
Background. Continuous experimentation (CE) has recently emerged as an established industry practice and as a research subject. Our aim is to study the application of CE and A/B testing in various industrial contexts. Objective. We wanted to investigate whether CE is used in different sectors of industry, by how it is reported in academic studies. We also wanted to explore the main topics research
The Internet of Things (IoT) paradigm brings an opportunity for advanced Demand Response (DR) solutions. It enables visibility and control on the various appliances that may consume, store or generate energy within a home. It has been shown that a centralized control on the appliances of a set of households leads to efficient DR mechanisms; unfortunately, such solutions raise privacy and scalabili
A coupling element is typically used to excite one of more characteristic modes of a structure to form some desired radiation properties. In particular, non-resonant coupling elements (CEs) are attractive, since it is electrically small and can be more conveniently integrated into the structure, such as the chassis of a mobile terminal. In this case, the chassis is the primary radiator of the mobi
In October 2016, the Special Interest Group on Theory of Characteristic Modes (TCM) initiated a coordinated effort to perform benchmarking work for characteristic mode (CM) analysis. The primary purpose is to help improve the reliability and capability of existing CM solvers and to provide the means for validating future tools. Significant progress has already been made in this joint activity. In
Astrocytic glutamate (Glt) uptake keeps brain interstitial Glt levels low. Within the astrocytes Glt is converted to glutamine (Gln), which is released and reconverted to Glt in neurons. The Glt-Gln cycle is energy demanding and impaired energy metabolism has been suggested to cause low interstitial Gln/Glt ratios. Using microdialysis (MD) measurements from visually noninjured cortex in 33 neuroin
Massive MIMO is a compelling wireless access concept that relies on the use of an excess number of base-station antennas, relative to the number of active terminals. This technology is a main component of 5G New Radio and addresses all important requirements of future wireless standards: a great capacity increase, the support of many simultaneous users, and improvement in energy efficiency. Massiv
We present an approach for connecting and coordinating distributed devices with different capabilities. More specifically, our research focuses on the design of an domain specific language that allows end-users to coordinate devices in pervasive systems.
Many companies and developers from OSS communities create open tools collaboratively in which software developers improve upon the code and share the changes within the community. Open tools (e.g., Jenkins, Gerrit, and Git) offer features or performance benefits that surpass their commercial counterparts in the core product development. Participation in OSS tools communities greatly dismantled the
Based on multi-link synchronous propagation measurements, we study the downlink performance of Coordinated Multi-point (CoMP) systems. The propagation measurements took place in an outdoor micro-cellular environment with two base stations (BSs) located 60 m apart, each equipped with two cross-polarized co-located antennas. We focus on the challenging case of having closely-located users with 0.5 m
The performance of wireless communication systems is fundamentally determined by wireless communication channel properties. Wireless vehicular communication channels exhibit multipath propagation and non-stationary channel statistics. Methods and tools for the repeatable test of wireless communication systems and signal processing algorithms in such environments are urgently needed to enable the d
Communication and collaboration is a major challenge for large-scale software development. Cognitive and psychological distance between individuals and teams affect this collaboration and can cause communications gaps. We propose a novel method for assessing distance between teams, and explore potential explanations for these distances. In an exploratory case study of the quality assurance departm
