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The digital cellular systems era started about thirty years ago with the release of the first digital cellphones. These first digital cellphones were very different from today’s slim and esthetic cellular pocket computers. They were not mass-produced in million units a day, and they were designed for radio performance rather than appearance. Today, all components are integrated inside the mobile p

[Context] Accurate time estimation is a critical aspect of predictable software engineering. Previous work shows that low source code quality increases the uncertainty in issue resolution times. [Objective] Our goal is to evaluate how developers' project experience and file ownership are related to issue resolution times. [Method] We mine 40 proprietary software repositories and conduct an observa

Background: The software engineering community has expressed growing concern regarding the need for more connections between research and practice. Despite the large amount of knowledge researchers generate, its impact on real-world practice is uncertain. Meanwhile, practitioners in industry often struggle to access and utilize relevant research outcomes that could inform and enhance their work. C

Most recent programming languages, such as Java, Python and Ruby, include a collection framework as part of their standard library (or runtime). The Java Collection Framework provides a number of collection classes, some of which implement the same abstract data type, making them interchangeable. Developers can therefore choose between several functionally equivalent options. Since collections hav

This special section of the IEEE OPEN JOURNAL OF CIRCUITS AND SYSTEMS (OJCAS) is dedicated to highlight the state-of-the-art research progress on circuits, systems, and algorithms associated with the design of beyond 5G (B5G) and 6G wireless systems.

CC-GLPDC codes are a class of generalized low-density parity-check (GLDPC) codes where the constraint nodes (CNs) represent convolutional codes. This allows for efficient decoding in the trellis with the forward-backward algorithm, and the strength of the component codes easily can be controlled by the encoder memory without changing the graph structure. In this letter, we extend the class of CC-G

Antennas are one of the key components that empower a new generation of wireless technologies, such as 5G and new radar systems. It has been shown that antenna design strategies based on modal theories represent a powerful systematic approach to design practical antenna systems with high performance. In this thesis, several innovative multi-antenna systems are proposed for wireless applications in

Acute respiratory distress syndrome (ARDS) is a life-threatening condition with mortality rates between 30-50%. Although in vitro models replicate some aspects of ARDS, small and large animal models remain the primary research tools due to the multifactorial nature of the disease. When using these animal models, histology serves as the gold standard method to confirm lung injury and exclude other

Static program analysis plays a crucial role in ensuring the quality and security of software applications by detecting and fixing bugs, and potential security vulnerabilities in the code. The use of declarative paradigms in dataflow analysis as part of static program analysis has become increasingly popular in recent years. This is due to its enhanced expressivity and modularity, allowing for a h

Orthogonal multi-user multiple-input multiple-output (MU-MIMO) channels allow for optimum performance with simplified precoding/equalization, and they achieve maximum multiplexing gain which is shared fairly among users. Reconfigurable intelligent surface (RIS) constitutes a promising cost-efficient solution to improve the wireless channel, since they consist of passive reflecting elements able to

After the commercial emergence of 5G, the research community is already putting its focus on proposing innovative solutions to enable the upcoming 6G. One important lesson put forth by 5G research was that scaling up the conventional multiple-input-multiple-output (MIMO) technology by increasing the number of antennas could be extremely beneficial for effectively multiplexing data streams in the s

The Last Interglacial (LIG) experienced substantial changes in seasonal insolation compared with the present day, which may have affected the hydrography and water-mass exchange in the North Sea and Baltic Sea region. Here we investigate the effects of solar radiation and greenhouse gas (GHG) forcing on the regional climate by analyzing model simulations of the LIG (127 ka BP), pre-industrial (PI,

Program analysis tools, from simple static semantic analysis by a compiler, to complex dynamic analyses of data flow and security, have become commonplace in modern day programming. Many of the simpler analyses, such as the afore- mentioned compiler checking or linters designed to enforce code style, may even go unnoticed or unconsidered by most users, ubiquitous as they are. Despite this, and des

Background: Driving automation systems (DAS), including autonomous driving and advanced driver assistance, are an important safety-critical domain. DAS often incorporate perceptions systems that use machine learning (ML) to analyze the vehicle environment. Aims: We explore new or differing requirements engineering (RE) topics and challenges that practitioners experience in this domain. Method: We

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

For the first time, the capacity gain of multisector cooperative multiple-input multiple-output(MIMO) using all three 120 degree sectors of a base station (BS) site is studied in a measured urban macrocellular environment at 2.65GHz. The results reveal that the mean uplink capacity gain exceeds 40% in as much as 1/4 of the coverage area, relative to the best single-sector link with no cooperation.

Electromagnetic vector spherical waves have been used recently to model antenna channel interaction and the available degrees of freedom in MIMO systems. However, there are no previous accounts of a method to estimate spherical wave coefficients from channel measurements. One approach, using a 3D positioner, is presented in this letter, both in theory and practice. Measurement results are present