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Photoinduced bimolecular charge transfer processes involving the iron(III) N-heterocyclic carbene (FeNHC) photosensitizer [Fe(phtmeimb)2]+ (phtmeimb = phenyltris(3-methyl-imidazolin-2-ylidene)borate) and triethylamine as well as N,N-dimethylaniline donors have been studied using optical spectroscopy. The full photocycle of charge separation and recombination down to ultrashort time scales was stud

Airborne Laser Scanning (ALS) is used to acquire three-dimensional (3D) city model data over large areas. However, because of the long ALS update cycle, building information models (BIM) could be utilized to maintain city models. In this study, we designed, implemented, and evaluated a methodology to formalize the integration of BIM data into city models. CityGML models were created from BIM data

In this paper, we study the trade-off between complexity and performance in massive MIMO systems with neural-network based digital pre-distortion (NN-DPD) blocks at the base station. In particular, we consider a multi-user massive MIMO system with per-antenna NN-DPDs, each with an adjustable NN architecture in terms of the size and the number of NN hidden layers. We first analyze the system perfor

Understanding the nature and origin of the precursor material to terrestrial planets is key to deciphering the mechanisms and timescales of planet formation1. Nucleosynthetic variability among rocky Solar System bodies can trace the composition of planetary building blocks2–5. Here we report the nucleosynthetic composition of silicon (μ30Si), the most abundant refractory planet-building element, i

Characteristic modes of arbitrary 2-D periodic systems are analyzed using scattering parameter data. This approach bypasses the need for periodic integral equations and allows for characteristic modes to be computed from generic simulation or measurement data. Example calculations demonstrate the efficacy of the method through comparison against a periodic method of moments (MoM) formulation for a

mmWave communication has come up as the unexplored spectrum for 5G services. With new standards for 5G NR positioning, more off-the-shelf platforms and algorithms are needed to perform indoor positioning. An object can be accurately positioned in a room either by using an angle and a delay estimate or two angle estimates or three delay estimates. We propose an algorithm to jointly estimate the ang

Open science aims to improve research accessibility, replicability, and consequently its quality. Empirical software engineering entails both data and artifacts, which may be shared more or less openly, to support transparency. However, the trade-offs involved in balancing the openness against integrity and secrecy concerns need methodological guidance. Aim. We aim to derive such advice, based on

Optimal inverse design, including topology optimization and evaluation of fundamental bounds on performance, which was introduced in Part 1, is applied to various antenna design problems. A memetic scheme for topology optimization combines local and global techniques to accelerate convergence and maintain robustness. Method-of-moments (MoMs) matrices are used to evaluate objective functions and al

INTRODUCTION: Tau positron emission tomography (PET) is a reliable neuroimaging technique for assessing regional load of tau pathology in the brain, but its routine clinical use is limited by cost and accessibility barriers. METHODS: We thoroughly investigated the ability of various machine learning models to predict clinically useful tau-PET composites (load and laterality index) from low-cost an

This paper proposes an alternative semi-analytical Fourier modal method adapted for general periodic anisotropic gratings made of dielectrics with moderate to low index profiles corresponding to materials ranging from conventional dielectric 3D printing materials to ceramic materials. The proposed method is closely related to classical Rigorous Coupled-Wave Analysis built on scattering matrices, h

The number of degrees of freedom is a crucial parameter in many electromagnetic problems. In for example modern communication systems spatial diversity is often employed through multiple beams to enhance capacity and reliability. However, while the degrees of freedom can be computed, their connection to physical quantities is not as easily understood. To address this issue, this paper proposes a s

Aiming for the sixth generation (6G) wireless communications, distributed massive multiple-input multiple-output (MIMO) systems hold significant potential for spatial multiplexing. In order to evaluate the ability of a distributed massive MIMO system to spatially separate closely spaced users, this paper presents an indoor channel measurement campaign. The measurements are carried out at a carrier

Battery-free IoT devices are becoming increasingly interesting for environmental and practical reasons, with ambient backscatter as one of the candidate technologies. We present a class of balanced transmission patterns for ambient backscatter communication (BSC) and evaluate their performance under different signal-to-interference ratios and fading conditions. These patterns allow for bit synchro

In this paper, we develop an uncertainty-aware decision-making and motion-planning method for an autonomous ego vehicle in forced merging scenarios, considering the motion uncertainty of surrounding vehicles. The method dynamically captures the uncertainty of surrounding vehicles by online estimation of their acceleration bounds, enabling a reactive but rapid understanding of the uncertainty chara

Hållbar utveckling är idag ett centralt begrepp och en vision inom alla tänkbara samhällsområden. Det utgör kärnan i svensk planeringslagstiftning. Såväl kommunalt översiktsplanearbete som regionalt utvecklingsarbete har tydliga perspektiv för en hållbar utveckling. Sveriges samhällsorganisation kan karaktäriseras av ett timglas med en stark stat, starka kommuner och en svag regional nivå i mitten

South Africa is a complex and dynamic society, with overwhelming and increasing problems with disaster risk in the vulnerable urban communities in and around its rapidly growing metropolitan centres. The purpose of this study is to improve the understanding of the challenges for disaster risk reduction in such communities. It focuses on the case of Imizamo Yethu, in the Western Cape, in order to b

Finger tapping to isochronous pacing stimuli is a well established experimental paradigm first described in the late 19th century. Two variables of common interest in rhythmic tapping tasks are timing variability and constant error. However, a difficulty when estimating these variables is that at interstimulus intervals longer than 2 seconds participants regularly overshoot the target interval and