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While Bayesian Optimization (BO) is a very popular method for optimizing expensive black-box functions, it fails to leverage the experience of domain experts. This causes BO to waste function evaluations on bad design choices (e.g., machine learning hyperparameters) that the expert already knows to work poorly. To address this issue, we introduce Bayesian Optimization with a Prior for the Optimum
Large intelligent surface (LIS) is a technology that extends massive MIMO by considering an even greater number of antennas distributed throughout vast areas. In order to be able to implement this technology, it is crucial to consider decentralized architectures so as to make the whole system scalable. We consider a LIS divided into several LIS panels of smaller size, which can be located far away
In this paper, we combine practically verified results from circuit theory with communication-theoretic laws. As a result, we obtain closed-form theoretical expressions linking fundamental system design and environment parameters with the power consumption of analog front ends (AFEs) for communication receivers. This collection of scaling laws and bounds is meant to serve as a theoretical referenc
The min-sum (MS) and approximate-min* (a-min*) algorithms are alternatives of the belief propagation (BP) algorithm for decoding low-density parity-check (LDPC) codes. To lower the BP decoding complexity, both algorithms compute two magnitudes at each check node (CN) and pass them to the neighboring variable nodes (VNs).In this work we propose a new algorithm, ga-min*, that generalizes the MS and
A pre-requisite for the design of wireless systems is the understanding of the propagation channel. While a wealth of propagation knowledge exists for bands below 6 GHz, the same can not be said for bands approaching millimeter-wave frequencies. In this paper, we present the design, implementation and measurement-based verification of a re-configurable 27.5-29.5 GHz channel sounder for measuring d
A reflective metasurface with reconfigurable beam is proposed for indoor wireless communications. It consists of 8 × 8 unit cells with tunable capacitors. By varying the capacitances, the reflective phase across the metasurface can be designed to facilitate different reflective angles for an incident wave. The simulation results show that the proposed reflective metasurface can deflect the incomin
Massive multiple-input multiple-out (MIMO) technology and mm wave are important technologies in 5G/6G to enhance the spectrum efficiency and system capacity. However, it has a lot of challenges in mm wave range, such as high hardware cost and power consumption in such systems. Hybrid beamforming is an interesting solution with less number of RF transvers than antennas. In this paper, we will prese
Large intelligent surfaces (LIS) have the potential to be the beyond-massive-MIMO solution, even further improving spectral efficiency, coverage, reliability and other performance measures. They also open up for entirely new services, such as precise localization, environment sensing, and wireless energy transfer. By constructing larger surfaces as a grid of panels, we can activate and deactivate
As 5G is entering maturity, the research interest has shifted towards 6G, and specially the new use cases that the future telecommunication infrastructure needs to support. These new use cases encompass much higher requirements, specifically: higher communication data-rates, larger number of users, higher accuracy in localization, possibility to wirelessly charge devices, among others.The radio ac
Predictions of cloud droplet activation in the late summertime (September) central Arctic Ocean are made using κ-Kohler theory with novel observations of the aerosol chemical composition from a high-resolution time-of-flight chemical ionization mass spectrometer with a filter inlet for gases and aerosols (FIGAERO-CIMS) and an aerosol mass spectrometer (AMS), deployed during the Arctic Ocean 2018 e
Dimethyl sulfide (DMS) influences climate via cloud condensation nuclei (CCN) formation resulting from its oxidation products (mainly methanesulfonic acid, MSA, and sulfuric acid, H2SO4). Despite their importance, accurate prediction of MSA and H2SO4 from DMS oxidation remains challenging. With comprehensive experiments carried out in the Cosmics Leaving Outdoor Droplets (CLOUD) chamber at CERN, w
We introduce the Atmospherically Relevant Chemistry and Aerosol box model ARCA box (v.1.2.2). It is a zero-dimensional process model with a focus on atmospheric chemistry and submicron aerosol processes, including cluster formation. A novel feature in the model is its comprehensive graphical user interface, allowing for detailed configuration and documentation of the simulation settings, flexible
The application of robotic solutions to small-batch production is challenging: economical constraints tend to dramatically limit the time for setting up new batches. Organizing robot tasks into modular software components, called skills, and allowing the assignment of multiple concurrent tasks to a single robot is potentially game-changing. However, due to cycle time constraints, it may be necessa
The performance and reliability of wireless communications at sea are often limited by the deep fades caused by the coherent sea surface reflection. In this paper, we show that by employing multiple antennas at the base station, the deep fades can be mitigated within a large communication range if the antennas are carefully spaced in the vertical direction. We derive a bound for the range where mi
Field-theory simulation by the complex Langevin method offers an alternative to conventional sampling techniques for exploring the forces driving biomolecular liquid–liquid phase separation. Such simulations have recently been used to study several polyampholyte systems. Here, we formulate a field theory corresponding to the hydrophobic/polar (HP) lattice protein model, with finite same-site repul
We prove that polynomial calculus (and hence also Nullstellensatz) over any field requires linear degree to refute that sparse random regular graphs, as well as sparse Erdős-Rényi random graphs, are 3-colourable.
We prove that unary Sherali-Adams requires proofs of size nΩ(d) to rule out the existence of an nΘ(1)-clique in Erdős-Rényi random graphs whose maximum clique is of size d ≤ 2 log n. This lower bound is tight up to the multiplicative constant in the exponent. We obtain this result by introducing a technique inspired by pseudo-calibration which may be of independent interest. The technique involves
This paper extends the application of quantile-based Bayesian inference to probability distributions defined in terms of quantiles of observable quantities. Quantile-parameterized distributions are characterized by high shape flexibility and parameter interpretability, making them useful for eliciting information about observables. To encode uncertainty in the quantiles elicited from experts, we p
We present Clog, a declarative language for describing static code checkers for C. Unlike other extensible state-of-the-art checker frameworks, Clog enables powerful interprocedural checkers without exposing the underlying program representation: Clog checkers consist of Datalog-style recursive rules that access the program under analysis via syntactic pattern matching and control flow edges only.
