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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
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
The design of antennas for compact multiple-input multiple-output (MIMO) terminals is a challenging feat, due to the space constraint and the physical structure of the terminal. The space constraint forces the antennas to be closely spaced, which degrades MIMO performance due to high signal correlation and low antenna efficiency. Moreover, the terminals are equipped with ground planes which furthe
For multiple antennas on a compact terminal chassis, chassis current excitation can severely increase mutual coupling between the antennas. This is because the same characteristic mode of the chassis may be strongly excited by more than one antenna. Here, we propose to use one antenna that exploits chassis excitation and introduce a second antenna that minimizes chassis excitation. In this way, an
The compactness of mobile terminals complicates the design of multiple antennas, since coupling among the antennas increases when they are placed in proximity of one another. While it is possible to mitigate coupling between closely spaced antennas, a tradeoff in bandwidth is required. In this paper, we highlight ground plane excitation as an additional dimension to consider in the design of multi
Traditionally, doctoral education is designed to train students to become skilled researchers in their respective disciplines. In many cases, however, doctoral graduates find themselves ill-prepared for their career choices. In this paper, we adopt a systematic approach to study the career preparation aspect of doctoral study in our home department. Our findings reveal several shortcomings in the
This paper demonstrates multiple-input-multiple-output (MIMO) throughput performance of a six-port dielectric resonator antenna (DRA) array for Wireless-LAN applications in a measured indoor office environment when a six-port dual-polarized patch array is used at the transmitter. The throughput was obtained using an IEEE802.11n/Draft 5.00 simulator for measured channels with different antenna and
In this paper, we study the potential benefits of downlink cooperative MIMO systems in cellular macrocell environments using a coherent measurement setup. Our results reveal that one of the two measured routes can leverage comparable signal strengths from the cooperating base stations to the mobile station and provide up to two-fold single user bitrate gain at the 50% cumulative probability level
Exploratory testing (ET) is a powerful and efficient way of testing software by integrating design, execution, and analysis of tests during a testing session. ET is often contrasted with scripted testing, and seen as a choice of either exploratory testing or not. In contrast, we pose that exploratory testing can be of varying degrees of exploration from fully exploratory to fully scripted. In line
For the 21st century, carbon cycle models typically project an increase of terrestrial carbon with increasing atmospheric CO2 and a decrease with the accompanying climate change. However, these estimates are poorly constrained, primarily because they typically rely on a limited number of emission and climate scenarios. Here we explore a wide range of combinations of CO2 rise and climate change and
This paper presents a robust timing synchronization method for full duplex orthogonal frequency division multiplexing (OFDM) systems based on Long Term Evolution (LTE). The proposed method contains two essential steps: 1) time alignment between the desired signal and self-interference 2) normalized synchronization peak (NSP) index switching. The time alignment is to make the difference in arrival
Explanations of leaf size variation commonly focus on water availability, yet leaf size also varies with latitude and elevation in environments where water is not strongly limiting. We provide the first conclusive test of a prediction of leaf energy balance theory that may explain this pattern: large leaves are more vulnerable to night-time chilling, because their thick boundary layers impede conv
Copy-paste-modify is a form of software reuse in which developers explicitly duplicate source code. This duplicated source code, amounting to a code clone, is adapted for a new purpose. Copy-paste-modify is popular among software developers, however, empirical evidence shows that it complicates software maintenance and increases the frequency of bugs. To allow developers to use copy-paste-modify w
Understanding and measuring security of softwarein terms of vulnerability metrics is important when reviewingand deciding between softwares. The large number of disclosedvulnerabilities will continue to expose software intensivesystems and products to attacks, and the choice of thirdparty software will affect stability and reliability of productsincorporating this software. We collect CVE da
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
