cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Evaluation of Load Matching and Grid Interaction Indexes of a Net Plus-Energy House in Brazil with a Hybrid PV System and Demand-Side Management
Creators: name: Almeida Dávi, G.
name: Castillo-Cagigal, M.
name: Caamaño-Martín, E.
name: Solano, J.
Publisher: name: WIP
Year: 2016
Subjects: PV Applications and Integration
Grid and Energy System Integration

description: 32nd European Photovoltaic Solar Energy Conference and Exhibition; 2697-2703
description: This paper analyzes four scenarios of PV system configuration and proposes an optimized hybrid PV
system size in order to improve Load Matching and Grid Interaction (LMGI) indicators, describing the yearly and
daily variations of the indexes. A net plus-energy house is modeled in EnergyPlus under humid subtropical and dry
tropical climates and electricity flows in the house and with the power grid are based on a high level battery
controller simulated with different PV-battery sizes. An economic analysis is presented through two supporting
schemes in order to perform analyses of Levelized Cost of Electricity (LCOE), grid parity and system payback time.
The results demonstrated the combination of load-shifting demand-side management and small-scale PV-battery
capacities provide improvements on building self-consumption and on the effects on the grid. The economic study
indicates the building reaches better profitability under current Brazilian net-metering scheme in scenarios without
batteries, reducing the payback time and LCOE sensibility analysis indicate the importance in reducing PV costs and
to promote financial incentives.
Playing nonlocal games with phases of quantum matter
Creators: name: Bulchandani, Vir B.
name: Burnell, Fiona J.
name: Sondhi, S. L.
Publisher: name: arXiv
Year: 2022
Subjects: subject: Quantum Physics (quant-ph)
subject: Statistical Mechanics (cond-mat.stat-mech)
subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: The parity game is an example of a nonlocal game: by sharing a Greenberger-Horne-Zeilinger (GHZ) state before playing this game, the players can win with a higher probability than is allowed by classical physics. The GHZ state of $N$ qubits is also the ground state of the ferromagnetic quantum Ising model on $N$ qubits in the limit of vanishingly weak quantum fluctuations. Motivated by this observation, we examine the probability that $N$ players who share the ground state of a generic quantum Ising model, which exhibits non-vanishing quantum fluctuations, still win the parity game using the protocol optimized for the GHZ state. Our main result is a modified parity game for which this protocol asymptotically exhibits quantum advantage in precisely the ferromagnetic phase of the quantum Ising model. We further prove that the ground state of the exactly soluble $d=1+1$ transverse-field Ising model can provide a quantum advantage for the parity game over an even wider region, which includes the entire ferromagnetic phase, the critical point and part of the paramagnetic phase. By contrast, we find examples of topological phases and symmetry-protected topological (SPT) phases of matter, namely the deconfined phase of the toric code Hamiltonian and the $\mathbb{Z}_2 \times \mathbb{Z}_2$ SPT phase in one dimension, that do not exhibit an analogous quantum advantage away from their fixed points.
description: v2: 18+6 pages, 4 figures, close to published version
Implications for the $ΔA_{FB}$ anomaly in ${\bar B}^0\to D^{*+}\ell^- {\barν}$ using a new Monte Carlo Event Generator
Creators: name: Bhattacharya, Bhubanjyoti
name: Browder, Thomas E.
name: Campagna, Quinn
name: Datta, Alakabha
name: Dubey, Shawn
name: Mukherjee, Lopamudra
name: Sibidanov, Alexei
Publisher: name: arXiv
Year: 2022
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: High Energy Physics - Experiment (hep-ex)
subject: FOS: Physical sciences

description: Recent experimental results in $B$ physics from Belle, BaBar and LHCb suggest new physics (NP) in the weak $b\to c$ charged-current and the $b\to s$ neutral-current processes. Here we focus on the charged-current case and specifically on the decay modes $\bar{B}^0\to D^{*+}\ell^- \barν$ with $\ell = e$ and $μ$. The world averages of the ratios $R_D$ and $R_D^{*}$ currently differ from the Standard Model (SM) predictions by $3.4σ$ while recently a new anomaly has been observed in the forward-backward asymmetry measurement, $A_{FB}$, in $ \bar{B}^0\to D^{*+}μ^- \barν$ decay. It is found that $ΔA_{FB} = A_{FB}(B\to D^{*} μν) - A_{FB} (B\to D^{*} e ν)$ is around $4.1σ$ away from the SM prediction in an analysis of 2019 Belle data. In this work we explore possible solutions to the $ΔA_{FB}$ anomaly and point out correlated NP signals in other angular observables. These correlations between angular observables must be present in the case of beyond the Standard Model physics. We stress the importance of $Δ$ type observables that are obtained by taking the difference of the observable for the muon and the electron mode. These quantities cancel form factor uncertainties in the SM and allow for clean tests of NP. These intriguing results also suggest an urgent need for improved simulation and analysis techniques in $\bar{B}^0\to D^{*+}\ell^- \barν$ decays. Here we also describe a new Monte Carlo Event-generator tool based on EVTGEN that we developed to allow simulation of the NP signatures in $\bar{B}^0\to D^{*+}\ell^- ν$, which arise due to the interference between the SM and NP amplitudes. We then discuss prospects for improved observables sensitive to NP couplings with 1, 5, 50, and 250 ab$^{-1}$ of Belle II data, which seem to be ideally suited for this class of measurements.
description: 22 pages, 9 figures, Version accepted for publication in PRD
On Spinors Transformations
Creators: name: Budinich, Marco
Publisher: name: arXiv
Year: 2016
Subjects: subject: Mathematical Physics (math-ph)
subject: FOS: Physical sciences

description: We begin showing that for even dimensional vector spaces $V$ all automorphisms of their Clifford algebras are inner. So all orthogonal transformations of $V$ are restrictions to $V$ of inner automorphisms of the algebra. Thus under orthogonal transformations $P$ and $T$ - space and time reversal - all algebra elements, including vectors $v$ and spinors $φ$, transform as $v \to x v x^{-1}$ and $φ\to x φx^{-1}$ for some algebra element $x$. We show that while under combined $PT$ spinor $φ\to x φx^{-1}$ remain in its spinor space, under $P$ or $T$ separately $φ$ goes to a 'different' spinor space and may have opposite chirality. We conclude with a preliminary characterization of inner automorphisms with respect to their property to change, or not, spinor spaces.
description: Minor changes to propositions 1 and 3
Solvepol: a reduction pipeline for imaging polarimetry data
Creators: name: Ramírez, Edgar A.
name: Magalhães, Antônio M.
name: Davidson, James W.
name: Pereyra, Antonio
name: Rubinho, Marcelo
Publisher: name: arXiv
Year: 2015
Subjects: subject: Instrumentation and Methods for Astrophysics (astro-ph.IM)
subject: FOS: Physical sciences

description: We present a newly, fully automated, data pipeline: Solvepol, designed to reduce and analyze polarimetric data. It has been optimized for imaging data from the Instituto de Astronomia, Geofisica e Ciencias Atmosfericas (IAG) of the University of Sao Paulo (USP), calcite Savart prism plate-based IAGPOL polarimeter. Solvepol is also the basis of a reduction pipeline for the wide-field optical polarimeter that will execute SOUTH POL, a survey of the polarized Southern sky. Solvepol was written using the interactive data language (IDL) and is based on the image reduction and analysis facility (IRAF) task pccdpack, developed by our polarimetry group. We present and discuss reduced data from standard stars and other fields and compare these results with those obtained in the IRAF environment. Our analysis shows that Solvepol, in addition to being a fully automated pipeline, produces results consistent with those reduced by pccdpack and reported in the literature.
description: Accepted for publication in PASP. 19 pages, 15 figures, 2 tables
Variational existence theory for hydroelastic solitary waves
Creators: name: Groves, Mark D.
name: Hewer, Benedikt
name: Wahlén, Erik
Publisher: name: arXiv
Year: 2016
Subjects: subject: Analysis of PDEs (math.AP)
subject: Mathematical Physics (math-ph)
subject: Pattern Formation and Solitons (nlin.PS)
subject: FOS: Mathematics
subject: FOS: Physical sciences
subject: 76B15 (Primary) 76B25, 74B20, 74F10, 35A15, 35R35 (Secondary)

description: This paper presents an existence theory for solitary waves at the interface between a thin ice sheet (modelled using the Cosserat theory of hyperelastic shells) and an ideal fluid (of finite depth and in irrotational motion) for sufficiently large values of a dimensionless parameter $γ$. We establish the existence of a minimiser of the wave energy ${\mathcal E}$ subject to the constraint ${\mathcal I}=2μ$, where ${\mathcal I}$ is the horizontal impulse and $0< μ\ll 1$, and show that the solitary waves detected by our variational method converge (after an appropriate rescaling) to solutions of he nonlinear Schrödinger equation with cubic focussing nonlinearity as $μ\downarrow 0$.
description: As accepted for publication
Experimental Analysis of the Performance of Façade-Integrated BIPV in Different Configurations
Creators: name: Van Den Broeck, G.
name: Parys, W.
name: Goverde, H.
name: Van Der Putten, S.
name: Poortmans, J.
name: Driesen, J.
name: Baert, K.
name: Saelens, D.
Publisher: name: WIP
Year: 2016
Subjects: PV Applications and Integration
PV in Buildings and the Environment

description: 32nd European Photovoltaic Solar Energy Conference and Exhibition; 2750-2754
description: The purpose of this paper is to quantitatively compare different façade-integrated BIPV configurations that relate to curtain walls and comprise both cold, ventilated façades and warm, unventilated façades and a different number of glazing sheets to improve aesthetics. Therefore, this paper introduces an experimental set-up and analyses the experimental results that were obtained over one year between May 2015-2016. Both temperatures and IV characteristics were continuously logged every 15 seconds. The different module configurations experience increased operating temperatures, optical losses and partial shading due to building-integration and are compared to a reference PV module over the observed time period in order to quantify the contribution of the different loss factors. The results show energy-yield losses, ranging from -11% to -27% as compared to the reference PV module.
Hydrodynamic Synchronisation of Chiral Microswimmers
Creators: name: Samatas, Sotiris
name: Lintuvuori, Juho S.
Publisher: name: arXiv
Year: 2022
Subjects: subject: Soft Condensed Matter (cond-mat.soft)
subject: Biological Physics (physics.bio-ph)
subject: Fluid Dynamics (physics.flu-dyn)
subject: FOS: Physical sciences

description: We study synchronization in bulk suspensions of spherical microswimmers with chiral trajectories using large scale numerics. The model is generic. It corresponds to the lowest order solution of a general model for self-propulsion at low Reynolds numbers, consisting of a nonaxisymmetric rotating source dipole. We show that both purely circular and helical swimmers can spontaneously synchronize their rotation. The synchronized state corresponds to velocity alignment with high orientational order in both the polar and azimuthal directions. Finally, we consider a racemic mixture of helical swimmers where intraspecies synchronization is observed while the system remains as a spatially uniform fluid. Our results demonstrate hydrodynamic synchronization as a natural collective phenomenon for microswimmers with chiral trajectories.
description: 7 + 8 pages, 6 + 6 figures
Optimising the Self-Consumption of Solar Powered Smart Micro Grids
Creators: name: Mahran, A.
name: Minde, A.
name: Peter, K.
name: Glatz-Reichenbach, J.
Publisher: name: WIP
Year: 2016
Subjects: PV Applications and Integration
Grid and Energy System Integration

description: 32nd European Photovoltaic Solar Energy Conference and Exhibition; 2691-2696
description: Due to the continuous rise of retail electricity price and the falling remuneration of photovoltaic (PV)
electricity feed-in tariffs (FIT), consumers who own PV installations are encouraged to increase their selfconsumption.
Furthermore, the intermittency of renewable energy resources (RES) hinders the exclusive reliance on
RES as a sustainable energy resource. Additionally, batteries still reveal several technical and economic
disadvantages when used to increase self-consumption. This research presents an approach to model a smart
neighbourhood by using a multi-agent system (MAS). The model’s consensus is to increase the self-consumption as
well as PV-based self-generation of an overall smart grid community. Furthermore, updated PV yield forecasts in
addition to recorded load consumption profiles are used as input to the MAS to invoke demand-side management and
urge participants to exchange their excess energy. In order to minimise the misfit between forecasted and measured
PV yields, a recursive optimisation algorithm is applied to improve future estimations, based on past prediction
errors. Results show that the self-consumption of single-users as well as the entire community – without using
batteries – can exceed 60% with a potential to achieve full grid independency when supported by electrical storage.
Moreover, community consumption can utilise all the electricity generated by PV, which leads to less grid congestion
by feed-ins from renewable energy sources.
Insights Into Deep Non-linear Filters for Improved Multi-channel Speech Enhancement
Creators: name: Tesch, Kristina
name: Gerkmann, Timo
Publisher: name: arXiv
Year: 2022
Subjects: subject: Audio and Speech Processing (eess.AS)
subject: Machine Learning (cs.LG)
subject: Sound (cs.SD)
subject: FOS: Electrical engineering, electronic engineering, information engineering
subject: FOS: Computer and information sciences

description: The key advantage of using multiple microphones for speech enhancement is that spatial filtering can be used to complement the tempo-spectral processing. In a traditional setting, linear spatial filtering (beamforming) and single-channel post-filtering are commonly performed separately. In contrast, there is a trend towards employing deep neural networks (DNNs) to learn a joint spatial and tempo-spectral non-linear filter, which means that the restriction of a linear processing model and that of a separate processing of spatial and tempo-spectral information can potentially be overcome. However, the internal mechanisms that lead to good performance of such data-driven filters for multi-channel speech enhancement are not well understood. Therefore, in this work, we analyse the properties of a non-linear spatial filter realized by a DNN as well as its interdependency with temporal and spectral processing by carefully controlling the information sources (spatial, spectral, and temporal) available to the network. We confirm the superiority of a non-linear spatial processing model, which outperforms an oracle linear spatial filter in a challenging speaker extraction scenario for a low number of microphones by 0.24 POLQA score. Our analyses reveal that in particular spectral information should be processed jointly with spatial information as this increases the spatial selectivity of the filter. Our systematic evaluation then leads to a simple network architecture, that outperforms state-of-the-art network architectures on a speaker extraction task by 0.22 POLQA score and by 0.32 POLQA score on the CHiME3 data.
description: Accepted version
Suppressed fluctuations as the origin of the static magnetic order in strained Sr$_2$RuO$_4$
Creators: name: Kim, Bongjae
name: Khmelevskyi, Sergii
name: Franchini, Cesare
name: Mazin, I. I.
Publisher: name: arXiv
Year: 2022
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: Combining first principle density functional calculations and Moriya's self-consistent renormalization theory, we explain the recently reported counterintuitive appearance of an ordered magnetic state in uniaxially strained Sr$_2$RuO$_4$ beyond the Lifshits transition. We show that strain weakens the quantum spin fluctuations, which destroy the static order, more strongly than the tendency to magnetism. A different rate of decrease of the spin fluctuations vs. magnetic stabilization energy promotes the onset of a static magnetic order beyond a critical strain.
Demand Side Power Management of a Grid Connected Solar PV System with Vanadium Redox Flow Battery Storage
Creators: name: Bhattacharjee, A.
name: Saha, H.
Publisher: name: WIP
Year: 2016
Subjects: PV Applications and Integration
Grid and Energy System Integration

description: 32nd European Photovoltaic Solar Energy Conference and Exhibition; 2713-2716
description: This paper presents an optimized energy management scheme for grid connected storage enabled solar PV power system dedicated towards demand side satisfaction under intermittent solar insolation. Vanadium Redox Flow Battery (VRFB) claims to be a promising energy storage technology to increase the supply reliability of large-scale PV applications due to its scalability, independent power and energy capacity and longer life cycle as compared to other conventional battery energy storages. During PV Power generation deficiency, the battery will be in discharging mode to supply the required load power and thus shaving the peak load in that period. The two way power flow is executed by placing a suitable bi-directional DC-DC converter between the point of common coupling (PCC) and the VRFB. A very low available state of charge (SOC) [1] less than 10% of VRFB storage and inadequate power generation from solar PV source together causes peak load demand dissatisfaction [2] which can be satisfied by importing power from the AC grid. Considering a DC load a suitable rectifier unit along with necessary filter is placed between the PCC and the grid. The efficiency of the solar PV source is enhanced by an efficient Maximum Power Point Tracking Technique (MPPT). The entire power management scheme [3] has been designed with the real life data of 1kW 6hr VRFB storage and the battery SOC [4-6] prediction algorithm is also implemented in MATLAB/Simulink environment to lengthen storage lifetime and the demand side reliability also. The presented research work has dealt with the simulation of optimized penetration of solar PV, VRFB and AC grid to smoothen the peak load demand for two practical case studies and the results are very useful for field validation.
Inertia Estimation Through Covariance Matrix
Creators: name: Bizzarri, Federico
name: del Giudice, Davide
name: Grillo, Samuele
name: Linaro, Daniele
name: Brambilla, Angelo
name: Milano, Federico
Publisher: name: arXiv
Year: 2022
Subjects: subject: Systems and Control (eess.SY)
subject: FOS: Electrical engineering, electronic engineering, information engineering

description: This work presents a technique to estimate on-line the inertia of a power system based on ambient measurements. The proposed technique utilizes the covariance matrix of these measurements and solves an optimization problem that fits such measurements to the synchronous machine classical model. We show that the proposed technique is adequate to accurately estimate the actual inertia of synchronous machines and also the virtual inertia provided by the controllers of converter-interfaced generators that emulate the behavior of synchronous machines. We also show that the proposed approach is able to estimate the equivalent damping of the classical synchronous machine model. This feature is exploited to estimate the droop of grid-following converters, which has a similar effect of the swing equation equivalent damping. The technique is comprehensively tested on a modified version of the IEEE 39-bus system as well as on a dynamic 1479-bus model of the all-island Irish transmission system.
Conditions in Which a Photovoltaic System Is More Viable Than a Low-Temperature Solar Thermal System
Creators: name: Lillo Bravo, I.
name: Silva Pérez, M.
name: Moreno, S.
name: Pérez, E.
Publisher: name: WIP
Year: 2016
Subjects: PV Applications and Integration
Grid and Energy System Integration

description: 32nd European Photovoltaic Solar Energy Conference and Exhibition; 2675-2678
description: Photovoltaic (PV) and low-temperature solar thermal (LT-STH) are the most widely used technologies
in the building sector. This study determines, depending on the most influential parameters, the conditions in which a
PV system is more beneficial than a LT-STH system from an economical, energetic and environmental point of view.
The parameter used for economically evaluated both technologies is the levelized cost of energy (LCOE). Moreover
the Greenhouse Gas Emissions factor is employed for an environmental evaluation. The main results shown on this
study reveal that in most cases PV is economically and environmentally more viable than LT-STH, although it would
be necessary to analyze the particular conditions of each site.
Photovoltaic Plant Orientation Strategies to Minimize Grid Exchange in Free Field and Building Integrated Setups
Creators: name: Ingenhoven, P.
name: Barchi, G.
name: Lovati, M.
name: Moser, D.
Publisher: name: WIP
Year: 2016
Subjects: PV Applications and Integration
Grid and Energy System Integration

description: 32nd European Photovoltaic Solar Energy Conference and Exhibition; 2679-2682
description: High penetration of photovoltaic generation might lead to problems in the distribution grid such as instability,
frequency deviations and reverse power flow. Parts of these problems can be mitigated by minimizing the exchange from
and to the grid. A possible strategy to minimize the power injected into the grid and to maximize the power used to supply
the load is to design a PV system in order to optimize the matching with the load. The classical strategy used in PV
installation is to maximize the production. However, to address load matching, power maximization is not anymore the
suitable approach. For this purpose, the aim of this work is to present two different strategies to optimize the orientation of
photovoltaic modules. The first considers every possible orientations and no restriction on the surface area as possible in a
free field installation. The second considers the surface of a building and tries to optimize the module orientations taking
into account typical constraints from the built environment (e.g. limited area, shading from nearby building, etc).
Nationwide Photovoltaic Hosting Capacity in the Finnish Electricity Distribution System
Creators: name: Lassila, J.
name: Tikka, V.
name: Haapaniemi, J.
name: Child, M.
name: Breyer, C.
name: Partanen, J.
Publisher: name: WIP
Year: 2016
Subjects: PV Applications and Integration
Grid and Energy System Integration

description: 32nd European Photovoltaic Solar Energy Conference and Exhibition; 2639-2648
description: In a large-scale integration of distributed generation (DG), a hosting capacity reflects the technical
limit for the adaption. Hosting capacity depends strongly on the existing electricity infrastructure and a profile of
electricity demand of end-customers. Hosting capacity and economic feasibility of large-scale integration of PV relate
strongly to each other. The target of the study is to illustrate what are the limits and possibilities for the large-scale
solar PV integration in Finland from the electricity distribution infrastructure perspective. The study utilizes a
nationwide database of buildings and roof surface areas, a case specific network data from actual distribution areas
and nationwide statistics of distribution system operators. Hourly-based load and generation data are used considering
geographical location and point of compass of individual buildings. The study shows that there is significant
residential rooftop solar PV capacity available according to the building and electricity infrastructure information.
The main outcome is that implementing this amount of solar PV in residential level does not bring significant
challenges for electricity distribution system.
Simulation of the Load Flow at the Transformer in Low Voltage Distribution Grids with a Significant Number of PV Systems Using Satellite-Derived Solar Irradiance
Creators: name: Ruf, H.
name: Schroedter-Homscheidt, M.
name: Beyer, H.G.
name: Heilscher, G.
Publisher: name: WIP
Year: 2016
Subjects: PV Applications and Integration
Grid and Energy System Integration

description: 32nd European Photovoltaic Solar Energy Conference and Exhibition; 2653-2658
description: A scheme using satellite-derived irradiance measurements to model the load flow of a medium-to-low
voltage transformer in a low voltage distribution grid area is described. This scheme is validated with measurements
at the transformer from a test site with 21 residential PV systems in the city of Ulm, Germany. The irradiance data are
provided by the SOLEMI, the Helioclim-3 and the CAMS Radiation Service. The load flow simulation model is
based on a PV model taking into account nominal power and location of the PV systems as provided by the
distribution system operator and orientation angles taken in high resolution from aerial laser-scan data. The load data
are assumed using load profile time series from standard load profiles and measured profiles. Modell quality is
assessed by a comparison of modelled and measured power. Average mean errors of power are found in the range of
14.0 % to 16.6 % and the RMSE is between 41.1 % and 42.3 % for the different input data sources. Overall, the study
indicates the usefulness and applicability of satellite-derived irradiance data for utility applications like load flow
monitoring of transformers in areas with a high amount of residential PV systems.
Improved empirical parametrizations of the $γ^\ast N \to Δ(1232)$ and $γ^\ast N \to N(1520)$ helicity amplitudes and the Siegert's theorem
Creators: name: Ramalho, G.
Publisher: name: arXiv
Year: 2016
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: High Energy Physics - Experiment (hep-ex)
subject: Nuclear Experiment (nucl-ex)
subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: In the nucleon electroexcitation reactions, $γ^\ast N \to R$, where $R$ is a nucleon resonance ($N^\ast$), the electric amplitude $E$, and the longitudinal amplitude $S_{1/2}$, are related by $E \propto \fracω{|{\bf q}|}S_{1/2}$, at the pseudo-threshold limit ($|{\bf q}| \to 0$), where $ω$ and $|{\bf q}|$ are respectively the energy and the magnitude of three-momentum of the photon. The previous relation is usually refereed as the Siegert's theorem. The form of the electric amplitude, defined in terms of the transverse amplitudes $A_{1/2}$ and $A_{3/2}$, and the explicit coefficients of the relation, depend on the angular momentum and parity ($J^P$) of the resonance $R$. The Siegert's theorem is the consequence of the structure of the electromagnetic transition current, which induces constraints between the electromagnetic form factors in the pseudo-threshold limit. In the present work, we study the implications of the Siegert's theorem for the $γ^\ast N \to Δ(1232)$ and $γ^\ast N \to N(1520)$ transitions. For the $γ^\ast N \to N(1520)$ transition, in addition to the relation between electric amplitude and longitudinal amplitude, we obtain also a relation between the two transverse amplitudes: $A_{1/2}= A_{3/2} /\sqrt{3}$, at the pseudo-threshold. % The constraints at the pseudo-threshold are tested for the MAID2007 parametrizations of the reactions under discussion. New parametrizations for the amplitudes $A_{1/2}$, $A_{3/2}$ and $S_{1/2}$, for the $γ^\ast N \to Δ(1232)$ and $γ^\ast N \to N(1520)$ transitions, valid for small and large $Q^2$, are proposed. The new parametrizations are consistent with both: the pseudo-threshold constraints (Siegert's theorem) and the empirical data.
description: Published in Phys. Rev. D. 21 pages, 13 figures, 5 tables
PV Integration and Price-Based Demand Side Management: Optimum Time-of-Use Tariffs
Creators: name: Philippou, N.
name: Venizelou, V.
name: Makrides, G.
name: Hadjipanayi, M.
name: Efthymiou, V.
name: Georghiou, G.E.
Publisher: name: WIP
Year: 2016
Subjects: PV Applications and Integration
Grid and Energy System Integration

description: 32nd European Photovoltaic Solar Energy Conference and Exhibition; 2664-2669
description: Growing electricity demand along with environmental concerns promote the use of renewable energy
sources (RES). In the Mediterranean region, the high solar energy potential renders the use of photovoltaic (PV)
technologies as one of the most favourable green sources. However, high penetration levels of distributed gridconnected
PV systems aggravate the intermittency and grid stability issues especially in cases where the grid is not
interconnected and there is a weak correlation between the electricity demand and PV generation. To this extent, a
price-based demand side management (DSM) tool has been developed in order to emulate the effectiveness of Time of
Use (ToU) tariffs. Through the application of such tariffs, demand response (DR) actions can be facilitated aiming to
partly mitigate PV operational issues and alleviate congestion problems. For this purpose, three hundred households in
Cyprus with grid-connected PV systems installed at their rooftops were equipped with smart meters (SMs) in order to
acquire consumption and production profile details of typical Cypriot prosumers. A sensitivity analysis was performed
where the Load Factor (LF) was compared under different peak clipping and load shifting scenarios.
Iwasawa theory for the symmetric square of a modular form
Creators: name: Loeffler, David
name: Zerbes, Sarah Livia
Publisher: name: arXiv
Year: 2015
Subjects: subject: Number Theory (math.NT)
subject: FOS: Mathematics
subject: 11F67, 11F80, 11G18

description: We construct a compatible family of global cohomology classes (an Euler system) for the symmetric square of a modular form, and apply this to bounding Selmer groups of the symmetric square Galois representation and its twists.
description: Updated version, to appear in J Reine Angew Math
Spatial modeling of all-cause mortality
Creators: name: Lhachimi, Stefan K.
Publisher: name: Humboldt-Universität zu Berlin, Wirtschaftswissenschaftliche Fakultät
Year: 2008
Subjects: subject: räumliche Statistik
subject: räumliche Demographie
subject: Sterblichkeit
subject: spatial error model
subject: mortality
subject: spatial statistics
subject: spatial demogaphy
subject: 310 Statistik
subject: 330 Wirtschaft

description: Der Tod macht alle Menschen gleich, dennoch sind nicht alle gleichmäßig betroffen. Unterschiede in der Sterblichkeit aufgrund des sozio-ökonomischen Status sind allgemein bekannt. Aber auch räumliche Disparitäten existieren. Es ist oft von großem Interesse Regionen mit außergewöhnlich hoher oder niedriger Mortalität zu identifizieren und die Determinanten für Sterblichkeitunterschiede zu modellieren. Darüberhinaus sind Sterblichkeitsdaten oft nur aggregiert erhältlich. Solche so genannte Lattice oder Areal-Daten benötigen allerdings spezielle statistische Methoden um die räumliche Struktur zu hinreichend zu modellieren. Eine Analyse der allgemeinen Sterblichkeit von Deutschen Bürgern im Alter von 20 bis 49 im Jahre 2004 wurde durchgeführt. Als Beobachtungseinheiten dienten die Landkreise bzw. Kreisfreien Städte. Mehrere erklärende Variablen wurden in einem Regressionmodel aufgenommen. Es konnte gezeigt werden, dass regionale Mortalität eine räumliche Korrelation aufweist. Weiterhin folgt die Sterblichkeit in Deutschland stärker einem Nord\Ost-Sued\West-Trend als einem einem Ost-West-Trend. Das Pro-Kopf-Einkommen hat einen grossen und signifikanten Einfluss auf die regionale Sterblichkeit, ähnliches gilt für Migration. Das verwendete statistische Model war ein spatial error model (auch als simultaneous autoregressive model bekannt) mit einer single contigutiy Nachbarschaftsstruktur.
description: Death is a unifying event for all mankind, but not everybody is equally affected. The mortality differential by socio-economic status is well established. But overall life expectancy differs by regions as well. The interest often lies in identifying regions with unusual high or low mortality and model external causes of mortality variation. Furthermore, mortality data is often only available at some aggregate level. Such lattice or area data, however, require particular statistical methods that are able to capture the spatial structure of the data. An analysis of all-cause mortality of German citizen between the ages of 20 to 49 in the year 2004 is conducted. The level of observation was the municipalities (Landkreise) and metropolitan areas (kreisfreie Staedte). Several explaining variables were tested in a spatial regression model. Most notably it could be shown that mortality data does exhibit spatial autocorrelation and that mortality in German follows rather a north/east to south/west trend than a mere east to west trend. Per capita income has a large and significant impact on mortality in the respective regions, the same is true for migration. The statistical model used was a spatial error model (sometimes called simultaneous autoregressive model) with a single contiguity neighborhood structure.
Selection of Weather Profile(s) for Testing Performance of SPV Pumps in Indian Climate
Creators: name: Yadav, K.
name: Sastry, O.S.
name: Bora, B.
name: Kumar, M.
name: Singh, R.
name: Kumar, A.
name: Prasad, B.
Publisher: name: WIP
Year: 2016
Subjects: PV Applications and Integration
PV Applications Without a Centralised Grid

description: 32nd European Photovoltaic Solar Energy Conference and Exhibition; 2528-2531
description: Indian climate is broadly divided into 4 climatic zones, Hot & dry, Hot & humid, Composite and cold &
Cloudy. Due to escalated targets for SPV water pumping systems installation in the country there is a large demand for
testing and certification of SPV pump samples. Indian test labs involved in testing and certifications are developing a
generalized radiation and temperature profiles to cover the above 4 climatic zones such that the certified pump provide
required performance in these climates. For testing samples quickly and yet ensure covering all climatic zones is with
minimum number of profiles is an involved and challenging problem. This paper presents two profiles of radiation and
temperature, representing summer and winter profiles, which is able to cover best and least performance of pump during
a year. Further, using these two profiles performance data of two sample pump systems evaluated in-terms of PV array
power output, quantity of water supplied (liters/ watt/ day), MPPT, Motor, pump and overall system efficiency.
On fractional sums of the divisor functions
Creators: name: Zhang, Wei
Publisher: name: arXiv
Year: 2022
Subjects: subject: Number Theory (math.NT)
subject: FOS: Mathematics

description: In this paper, we consider the fractional sum of the divisor functions. We can improve previous results considered by Bordellés \cite{Bo} and Liu-Wu-Yang \cite{LWY}.
Model-Based Design and Simulation of Control Strategies to Maximize the PV Hosting Capacity in Isolated Diesel Networks - Using Solar Short-Term Forecasts for Predictive Control of Diesel Generation
Creators: name: Peters, D.
name: Völker, R.
name: Kilper, T.
name: Calais, M.
name: Schmidt, T.
name: Carter, C.
name: Von Maydell, K.
name: Agert, C.
Publisher: name: WIP
Year: 2016
Subjects: PV Applications and Integration
PV Applications Without a Centralised Grid

description: 32nd European Photovoltaic Solar Energy Conference and Exhibition; 2532-2535
description: Increasing Photovoltaic (PV) system penetration in small, isolated networks faces a number of
technical, regulatory and economic challenges but also opportunities. The replacement of costly and polluting diesel
generation is highly desirable, however, a key technical issue is system stability, particularly on intermittent cloudy
days. In this context, the step load response capability and spinning reserve provided by diesel generation are critical
to cover for the sudden loss of PV power. This work develops and tests the application of short-term forecasts using
‘sky imagers’ in the control of generation capacity. The benefits for system stability shall be examined using an
example isolated network modeled in PowerFactory that simulates frequency and voltage at the generator busbar. To
reduce forecast errors, ensemble forecasts for all PV systems in the network are used. The results show a favourable
low impact of PV power on voltage and frequency, if realistic ramp rates for dispersed PV systems are used. The
envisaged fuel savings from reducing spinning reserve requirements are achieved but stay below 1 %. With the
inclusion of short-term storage capacity, further benefits are expected. In addition, the high dependency of possible
PV penetration on generator dispatch and loading is shown.
ZigZag Structure in Façade Optimizes PV Yield While Aesthetics Are Preserved
Creators: name: Valckenborg, R.M.E.
name: Van De Wall, W.
name: Folkerts, W.
name: Hensen, J.L.M.
name: De Vries, A.
Publisher: name: WIP
Year: 2016
Subjects: PV Applications and Integration
PV in Buildings and the Environment

description: 32nd European Photovoltaic Solar Energy Conference and Exhibition; 2486-2491
description: In the Netherlands, the possibilities for façade PV applications draw more attention lately due to a
combination of government incentives, declining PV-module prices and upcoming legislation from the European NZEBdirective
(2010/31/EU). In this context, start-up company Wallvision has introduced a ZigZag structured façade in which
the PV-modules are hidden from ground level, and the decorative panels are customized to the aesthetical preferences of
the architect. Understanding the PV-yield as a function of the geometry and other system components is crucial. For this
purpose a customized geometrical model has been developed that can handle the varying solar path and the specular and
diffuse reflection of the decorative panels. The experimental validation of the model is done with a newly built test façade
(of 3 x 3 ZigZag cassettes, area ~ 20m2) in the SolarBEAT outdoor research facility of SEAC. Measurements include the
irradiance at various points and kWh-yield per minute time interval. The aesthetic aspect of the ZigZag façade is as
important as the PV-performance part of the product, and is therefore included in this paper.
Quantification of Glare from Sunlight Reflected on Solar Installations
Creators: name: Battaglia, M.
name: Ruesch, F.
name: Bohren, A.
name: Brunold, S.
Publisher: name: WIP
Year: 2016
Subjects: PV Applications and Integration
PV in Buildings and the Environment

description: 32nd European Photovoltaic Solar Energy Conference and Exhibition; 2503-2507
description: Several methods to assess glare in an indoor and outdoor environment are reviewed. Furthermore,
measurements of the reflection properties of different glass types and other materials used in the building envelope
are presented. The bidirectional reflectance distribution function (BRDF) is used to characterize the different
materials and to evaluate their potential of creating discomfort glare in combination with reflected sunlight according
to different thresholds. The results are used to discuss the applicability of the different thresholds for developing a
reliable framework for the classification of reflections. In addition, recommendations for which glass type performs
best with respect to glare are given for different situations.
Multi-granularity Item-based Contrastive Recommendation
Creators: name: Xie, Ruobing
name: Qiu, Zhijie
name: Zhang, Bo
name: Lin, Leyu
Publisher: name: arXiv
Year: 2022
Subjects: subject: Information Retrieval (cs.IR)
subject: FOS: Computer and information sciences

description: Contrastive learning (CL) has shown its power in recommendation. However, most CL-based recommendation models build their CL tasks merely focusing on the user's aspects, ignoring the rich diverse information in items. In this work, we propose a novel Multi-granularity item-based contrastive learning (MicRec) framework for the matching stage (i.e., candidate generation) in recommendation, which systematically introduces multi-aspect item-related information to representation learning with CL. Specifically, we build three item-based CL tasks as a set of plug-and-play auxiliary objectives to capture item correlations in feature, semantic and session levels. The feature-level item CL aims to learn the fine-grained feature-level item correlations via items and their augmentations. The semantic-level item CL focuses on the coarse-grained semantic correlations between semantically related items. The session-level item CL highlights the global behavioral correlations of items from users' sequential behaviors in all sessions. In experiments, we conduct both offline and online evaluations on real-world datasets, verifying the effectiveness and universality of three proposed CL tasks. Currently, MicRec has been deployed on a real-world recommender system, affecting millions of users. The source code will be released in the future.
description: 17 pages, under review
Probabilistic Evaluation of UK Domestic Solar Photovoltaic Systems: An Integrated Geographical Information System PV Estimation Tool
Creators: name: Leicester, P.A.
name: Doylend, N.
name: Rowley, P.
Publisher: name: WIP
Year: 2016
Subjects: PV Applications and Integration
Grid and Energy System Integration

description: 32nd European Photovoltaic Solar Energy Conference and Exhibition; 2459-2465
description: It is shown how key predictor parameters for the spatial estimation of PV yield, self-consumption and
thereby economic and social indicators can be extracted from a GIS system and introduced into a Bayesian Network
model. This model endogenises the uncertainties and incorporates spatial variability inherent in these parameters.
Empirical monthly and annual yield measurements obtained from over 600 PV installations have been obtained and
compared with estimated yields obtained by two key solar tools used for performance estimation in the UK – these
are PVGIS and the UK Government’s Standard Assessment Procedure (SAP) for domestic buildings. Mean bias
estimates and root mean square error estimations were obtained for each tool and the results used to construct an
uncertainty distribution in PV yield prediction given key input parameters such as system rating, orientation and tilt.
This uncertainty was used to furnish a probabilistic graphical model with a prior distribution for PV yield estimation.
This was integrated into a Geographical Information (GIS) system furnished with roof and building stock parameters
including roof attributes obtained from lidar data. Elements held in a vector layer of the GIS system can be selected
and the resultant distributions of input parameters automatically fed to the model to yield a posterior distribution of
the PV yield. The model is able to propagate the yield uncertainty to other probabilistic models, including ones which
predict the internal rate of return and self-consumption. The latter is in turn predicted by empirical marginal
distributions of domestic electricity consumption. Thus with a given posterior distributions of PV yield, new posterior
distributions for the internal rate of return, self-consumption and carbon emission savings are automatically
calculated. By integration with GIS this novel approach allows the spatial analysis of the uncertainty pertaining to
representative risk factors for PV adoption in the UK, and facilitate the estimation by installers, investors, and local
authorities in a manner which endogenises uncertainty.
Entanglement entropies and fermion signs of critical metals
Creators: name: Kaplis, N.
name: Krüger, F.
name: Zaanen, J.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: The fermion sign problem is often viewed as a sheer inconvenience that plagues numerical studies of strongly interacting electron systems. Only recently, it has been suggested that fermion signs are fundamental for the universal behavior of critical metallic systems and crucially enhance their degree of quantum entanglement. In this work we explore potential connections between emergent scale invariance of fermion sign structures and scaling properties of bipartite entanglement entropies. Our analysis is based on a wavefunction ansatz that incorporates collective, long-range backflow correlations into fermionic Slater determinants. Such wavefunctions mimic the collapse of a Fermi liquid at a quantum critical point. Their nodal surfaces -- a representation of the fermion sign structure in many-particle configurations space -- show fractal behavior up to a length scale $ξ$ that diverges at a critical backflow strength. We show that the Hausdorff dimension of the fractal nodal surface depends on $ξ$, the number of fermions and the exponent of the backflow. For the same wavefunctions we numerically calculate the second Rényi entanglement entropy $S_2$. Our results show a cross-over from volume scaling, $S_2\sim \ell^θ$ ($θ=2$ in $d=2$ dimensions), to the characteristic Fermi-liquid behavior $S_2\sim \ell\ln \ell$ on scales larger than $ξ$. We find that volume scaling of the entanglement entropy is a robust feature of critical backflow fermions, independent of the backflow exponent and hence the fractal dimension of the scale invariant sign structure.
description: 9.5 pages, 10 figures
On uniform approximation to successive powers of a real number
Creators: name: Schleischitz, Johannes
Publisher: name: arXiv
Year: 2016
Subjects: subject: Number Theory (math.NT)
subject: FOS: Mathematics
subject: 11H06, 11J13, 11J25

description: We establish new inequalities involving classical exponents of Diophantine approximation. This allows for improving on the work of Davenport, Schmidt and Laurent concerning the maximum value of the exponent $\hatλ_{n}(ζ)$ among all real transcendental $ζ$. In particular we refine the estimation $\hatλ_{n}(ζ)\leq \lceil n/2\rceil^{-1}$ due to M. Laurent by $\hatλ_{n}(ζ)\leq \hat{w}_{\lceil n/2\rceil}(ζ)^{-1}$ for all $n\geq 1$, and for even $n$ we replace the bound $2/n$ for $\hatλ_{n}(ζ)$ first found by Davenport and Schmidt by roughly $\frac{2}{n}-\frac{1}{2n^{3}}$, which provides the currently best known bounds when $n\geq 6$.
description: 18 pages; Two minor inaccuracies in the proof of Lemma 3.2 were corrected (false in printed version!). (66) was slightly changed, and in the last highlighted equuality the index should be m instead of n
Enhanced symmetry-breaking tendencies in the $S=1$ pyrochlore antiferromagnet
Creators: name: Hagymási, Imre
name: Noculak, Vincent
name: Reuther, Johannes
Publisher: name: arXiv
Year: 2022
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: We investigate the ground-state properties of the nearest-neighbor $S=1$ pyrochlore Heisenberg antiferromagnet using two complementary numerical methods, density-matrix renormalization group (DMRG) and pseudofermion functional renormalization group (PFFRG). Within DMRG, we are able to reliably study clusters with up to 48 spins by keeping 20 000 SU(2) states. The investigated 32-site and 48-site clusters both show indications of a robust $C_3$ rotation symmetry breaking of the ground-state spin correlations and the 48-site cluster additionally features inversion symmetry breaking. Our PFFRG analysis of various symmetry-breaking perturbations corroborates the findings of either $C_3$ or a combined $C_3$/inversion symmetry breaking. Moreover, in both methods the symmetry-breaking tendencies appear to be more pronounced than in the $S=1/2$ system.
description: 8 pages, 6 figures