cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Impact of Ribbon Specification and Handling during PV Module Manufacturing to Module Reliability
Creators: name: Schneider, A.
name: Farneda, R.
name: Link, T.
name: Fidalgo, J.I.
name: Schmauder, J.
name: Harney, R.
Publisher: name: WIP
Year: 2016
Subjects: Operation, Performance, Reliability and Sustainability of Photovoltaics
PV Cells and Modules

description: 32nd European Photovoltaic Solar Energy Conference and Exhibition; 1583-1588
description: The current BOM of crystalline silicon solar cell modules appear to be very small if compared to other
products for example in consumer electronics or car industry. Nonetheless almost each item listed in the BOM is a
key material for the lifetime of +20 years for PV panels. Currently available characterization equipment being used
by module makers only partly allows to give a clear interpretation and statement of the capability of the module to
withstand climatic impact such as thermo-mechanical stress for many years. In most cases defects on cell level such
as cracks or metallization defects grow in time and degrade the fill factor hence the power on a longer time-scale.
This paper investigates the effect of ribbon thickness to the for EL invisible defect rate and evaluates how this effect
increases by applying thermo-mechanical stress to the module. Clear measures are presented on how such stress
hence power degradation can be reduced. The results indicate that depending on the encapsulation layer thickness a
critical ribbon thickness exists which shall not be exceeded. In this situation the ribbon yield strength has only a
negligible influence on the defect reduction. Beside a ribbon thickness reduction the encapsulation foil thickness can
be increased or the lamination membrane pressure accordingly adjusted. The amount of defects appearing only after
thermo-mechanical stress are a very good indication for the expected power losses and can be used to a certain degree
as a prediction for such.
RenyiCL: Contrastive Representation Learning with Skew Renyi Divergence
Creators: name: Lee, Kyungmin
name: Shin, Jinwoo
Publisher: name: arXiv
Year: 2022
Subjects: subject: Machine Learning (stat.ML)
subject: Machine Learning (cs.LG)
subject: FOS: Computer and information sciences

description: Contrastive representation learning seeks to acquire useful representations by estimating the shared information between multiple views of data. Here, the choice of data augmentation is sensitive to the quality of learned representations: as harder the data augmentations are applied, the views share more task-relevant information, but also task-irrelevant one that can hinder the generalization capability of representation. Motivated by this, we present a new robust contrastive learning scheme, coined RényiCL, which can effectively manage harder augmentations by utilizing Rényi divergence. Our method is built upon the variational lower bound of Rényi divergence, but a naïve usage of a variational method is impractical due to the large variance. To tackle this challenge, we propose a novel contrastive objective that conducts variational estimation of a skew Rényi divergence and provide a theoretical guarantee on how variational estimation of skew divergence leads to stable training. We show that Rényi contrastive learning objectives perform innate hard negative sampling and easy positive sampling simultaneously so that it can selectively learn useful features and ignore nuisance features. Through experiments on ImageNet, we show that Rényi contrastive learning with stronger augmentations outperforms other self-supervised methods without extra regularization or computational overhead. Moreover, we also validate our method on other domains such as graph and tabular, showing empirical gain over other contrastive methods.
description: Camera-ready version
City of Words. A Multimodal Collaboration in ‘Writing Urban Places’
Creators: name: Pauwels, Luc
name: Moloney, Anna Ryan
Publisher: name: Writingplace
Year: 2021

description: This contribution is a collaborative effort of two scholars from different disciplinary and geographic backgrounds joined by an interest in producing and communicating urban narratives. Their partnership resulted in an experiment that combines aspects of different research and communication methods into a hybrid end-result: a collaborative multimodal essay. First, the methodological particularities of this collaborative effort will be discussed and situated within number of established and emerging visual methods: the blending of methods, the researcher roles, the distinct modes of expression and the different positions vis-a-vis the site under scrutiny (‘visitor’ versus ‘resident’; ‘outsider’ versus ‘insider’). This section will then be followed by the actual multimodal essay on the city of Limerick as a distinct form of scholarly communication balancing between art and science.
description: Writingplace, No. 5 (2021): Narrative Methods for Writing Urban Places
Preliminary Results of the Fifth International Spectroradiometer Comparison for Improved Solar Spectral Irradiance Measurements
Creators: name: Galleano, R.
name: Zaaiman, W.
name: Alonso-Álvarez, D.
name: Minuto, A.
name: Ferretti, N.
name: Fucci, R.
name: Marzoli, M.
name: Manni, L.
name: Halwachs, M.
name: Friederichs, M.
name: Plag, F.
name: Friedrich, D.
name: Haverkamp, E.
Publisher: name: WIP
Year: 2016
Subjects: Operation, Performance, Reliability and Sustainability of Photovoltaics
Solar Resource and Forecasting

description: 32nd European Photovoltaic Solar Energy Conference and Exhibition; 1465-1469
description: The wider portfolio of today's available photovoltaic (PV) technologies on the market makes the
measurement of the spectral content of the incoming sun or artificial light a key parameter for the characterization,
calibration, and energy yield estimation of these devices. At present there is a growing request for harmonization of
good measurement practices and for knowledge transfer in the field of spectrally resolved solar radiation for solar
energy applications (e.g. photovoltaics) in order to make these measurements comparable and directly traceable to SI
units. A group of European research institutes active in the PV field for research, characterization and engineering,
set up the fifth comparison of spectroradiometers for solar spectrum measurements. In this paper the preliminary
results of such exercise are reported.
Photovoltaic Emulator for High-Performance Multi-Substring Simulations
Creators: name: Mai, T.D.
name: De Breucker, S.
name: Baert, K.
name: Van Tichelen, P.
name: Driesen, J.
Publisher: name: WIP
Year: 2016
Subjects: Operation, Performance, Reliability and Sustainability of Photovoltaics
Balance of System Components

description: 32nd European Photovoltaic Solar Energy Conference and Exhibition; 1522-1527
description: This paper presents the design and implementation of a photovoltaic (PV) emulator which can act as a multiple
sub-string PV module under various irradiation levels, shading conditions and cell temperatures. Based on one-cell diode model
approach, the modeling of a PV module takes into account the avalanche breakdown characteristics at the level of shaded
cells as well as at substring level. Operation tests of the developed emulator are performed with electronic loads and a DC-DC
converter.
Thick Photographic Descriptions
Creators: name: Van Haeren, Kristen
Publisher: name: Writingplace
Year: 2021

description: This paper explores how ‘nature’ – in the form of the landscapes of two housing estates in Copenhagen – was a central part of the vision of establishing a good life for every citizen: nature was being valued as an essential amenity and common ground for the creation of the new welfare vision for all. Through an analysis of, and engagement with, historical documents – as well as situated photographic modes of inquiry – this investigation into welfare landscapes focuses on the less-acknowledged but vital forces that shape the green outdoor areas of the housing estates, framing details to emphasize the specificity of place and depicting a landscape for living where humans were central. This way of working can offer insights into multifarious spatial grounds, diverse interpretations of green spaces, and the construction of humane living environments designed for access to nature – but also provide civic opportunities and affordances for gathering, play, community, privacy, personal development and the like – all within these welfare landscapes.
description: Writingplace, No. 5 (2021): Narrative Methods for Writing Urban Places
The sympathetic imagination in the novels of J.M. Coetzee
Creators: name: Heister, Hilmar
Publisher: name: Humboldt-Universität zu Berlin, Kultur-, Sozial- und Bildungswissenschaftliche Fakultät
Year: 2015
Subjects: subject: Literatur
subject: Empathie
subject: Coetzee
subject: Breithaupt
subject: Sympathie
subject: Spiegelneuronen
subject: Neurowissenschaften
subject: Narration
subject: Zaboura
subject: Empathy
subject: Sympathetic Imagination
subject: Sympathy
subject: Mirror Neurons
subject: Neurosciences
subject: FOS: Clinical medicine
subject: Literature
subject: Novel
subject: 800 Literatur, Rhetorik, Literaturwissenschaft
subject: 52 Englische Sprach- und Literaturwissenschaft

description: In dieser Studie wird umfassend untersucht, wie sich die sympathetic imagination im Werk von J.M. Coetzee entwickelt. Zugrunde liegt die Annahme, dass die Art und Weise wie J.M. Coetzee seine sympathetic imagination zum Einsatz bringt die Empathiefähigkeit des Lesers zu steigern vermag. Ausgangspunkt für die Untersuchung und deren zentrale Analysekategorien für die Besprechung der Romane Coetzees ist ein Blick auf Spiegelneuronen als neuronale Grundlage für Empathie, ein relative neues und stetig sich erweiterndes Feld. Geteilte Aufmerksamkeit (shared attention) und Perspektivübernahme (perspective-taking) bilden den Mittelpunkt bei neurowissenschaftlichen Diskussionen über den Zusammenhang zwischen Spiegelneuronen und Empathie. Eine Analyse von Coetzees Romanen zeigt, dass in seiner Literatur vergleichbare Mechanismen zur Wirkung kommen.
description: The following study attempts a comprehensive evaluation of how the sympathetic imagination evolves in the works of J.M. Coetzee. The underlying assumption is that the way Coetzee employs his sympathetic imagination in his fiction enhances the reader’s empathetic capabilities. A starting point for the central categories of analysis and the close readings of his novels will be a brief exploration of the neuronal basis of empathy as discussed in the context of the discovery of and continuously extending research on mirror neurons as the neurological basis for empathy. Shared attention and perspective-taking constitute the focus of neuroscientific discussions of the connection between empathy and mirror neurons. A close look at Coetzee’s fiction will reveal comparable mechanisms in literary representation.
The Readjusted Arabesque
Creators: name: Restrepo Restrepo, Esteban
Publisher: name: Writingplace
Year: 2021

description: The architect is not the only artist who conceives architecture. As the most common spatial and material framework in which human life takes place, architecture also appears in other arts like painting, cinema, theatre and literature, where it is an unavoidable subject of conception and reflection. Among those arts, it is on the architectures that are present in literary texts that we will focus in this article. Unlike the architect, the writer conceives architecture with the technical conditions and the aesthetic particularities of the literary medium. Thus, the experience we make of literary architectures radically differs from the one we make of built architectures, which can be experienced first-hand and navigated at will. To appraise a literary architecture this contribution will use two analytical categories from Gérard Genette’s narratology, namely: the Voice or the situation of the narrator in relation to the story he tells, and its implications in the representation of architecture; and the Order or the sequences in which architecture is represented during the narration. We will use both categories to analyse Kafka’s short story The Bridge (Die Brücke).
description: Writingplace, No. 5 (2021): Narrative Methods for Writing Urban Places
Observation of vibrational dynamics of orientated Rydberg-atom-ion molecules
Creators: name: Zou, Yi-Quan
name: Berngruber, Moritz
name: Anasuri, Viraatt S. V.
name: Zuber, Nicolas
name: Meinert, Florian
name: Löw, Robert
name: Pfau, Tilman
Publisher: name: arXiv
Year: 2022
Subjects: subject: Atomic Physics (physics.atom-ph)
subject: Quantum Gases (cond-mat.quant-gas)
subject: FOS: Physical sciences

description: Vibrational dynamics in conventional molecules usually takes place on a timescale of picoseconds or shorter. A striking exception are ultralong-range Rydberg molecules, for which dynamics is dramatically slowed down as a consequence of the huge bond length of up to several micrometers. Here, we report on the direct observation of vibrational dynamics of a recently observed Rydberg-atom-ion molecule. By applying a weak external electric field of a few mV/cm, we are able to control the orientation of the photoassociated ultralong-range Rydberg molecules and induce vibrational dynamics by quenching the electric field. A high resolution ion microscope allows us to detect the molecule's orientation and its temporal vibrational dynamics in real space. Our study opens the door to the control of molecular dynamics in Rydberg molecules.
description: 7 pages, 4 figures
Narrative Methods for Writing Urban Places
Creators: name: Havik, Klaske
name: Niculae, Lorin
name: Meija Hernandez, Jorge
name: Proosten, Mark
Publisher: name: Writingplace
Year: 2021

description: This fifth issue of the Writingplace Journal examines different narrative methods, understood as procedures, techniques or ways of relating or recounting events, and how they can be used to appraise and imagine the city. The editorial process of the issue has been developed within the context of the EU-funded COST Action ‘Writing Urban Places’,1 a multidisciplinary network of researchers who are interested in developing new narratives for the European city. By recognizing the value of urban narratives – stories rich in information regarding citizens’ sociospatial practices, perceptions, hopes and ambitions – the network seeks to foster and preserve the democratic, and therefore inclusive, nature of the modern European city.
description: Writingplace, No. 5 (2021): Narrative Methods for Writing Urban Places
Cluster expansion formulas in type A
Creators: name: Yurikusa, Toshiya
Publisher: name: arXiv
Year: 2016
Subjects: subject: Representation Theory (math.RT)
subject: Combinatorics (math.CO)
subject: FOS: Mathematics

description: The aim of this paper is to give analogs of the cluster expansion formula of Musiker and Schiffler for cluster algebras of type A with coefficients arising from boundary arcs of the corresponding triangulated polygon. Indeed, we give three cluster expansion formulas by perfect matchings of angles in triangulated polygon, by discrete subsets of arrows of the corresponding ice quiver and by minimal cuts of the corresponding quiver with potential.
description: 15 pages
Scale free chaos in the confined Vicsek flocking model
Creators: name: González-Albaladejo, R.
name: Carpio, A.
name: Bonilla, L. L.
Publisher: name: arXiv
Year: 2022
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: Chaotic Dynamics (nlin.CD)
subject: Biological Physics (physics.bio-ph)
subject: FOS: Physical sciences

description: The Vicsek model encompasses the paradigm of active dry matter. Motivated by collective behavior of insects in swarms, we have studied finite size effects and criticality in the three dimensional, harmonically confined Vicsek model. We have discovered a phase transition that exists for appropriate noise and small confinement strength. On the critical line of confinement versus noise, swarms are in a state of scale-free chaos characterized by minimal correlation time, correlation length proportional to swarm size and topological data analysis. The critical line separates dispersed single clusters from confined multicluster swarms. Scale-free chaotic swarms occupy a compact region of space and comprise a recognizable `condensed' nucleus and particles leaving and entering it. Susceptibility, correlation length, dynamic correlation function and largest Lyapunov exponent obey power laws. The critical line and a narrow criticality region close to it move simultaneously to zero confinement strength for infinitely many particles. At the end of the first chaotic window of confinement, there is another phase transition to infinitely dense clusters of finite size that may be termed flocking black holes.
description: 24 pages, 26 figures, revtex
Fast All-Sky Radiation Model for Solar Applications (FARMS): A Brief Overview of Mechanisms, Performance, and Applications
Creators: name: Xie, Y.
name: Sengupta, M.
Publisher: name: WIP
Year: 2016
Subjects: Operation, Performance, Reliability and Sustainability of Photovoltaics
Solar Resource and Forecasting

description: 32nd European Photovoltaic Solar Energy Conference and Exhibition; 1462-1464
description: Solar radiation can be computed using radiative transfer models, such as the Rapid Radiation Transfer Model
(RRTM) and its general circulation model applications (RRTMG), and used for various energy applications. Due to the
complexity of computing radiation fields in aerosol and cloudy atmospheres, simulating solar radiation can be extremely
time-consuming, though many approximations, e.g., two-stream approach and delta-M truncation scheme, can be utilized.
To provide a new fast option for computing solar radiation, we developed the Fast All-sky Radiation Model for Solar
applications (FARMS) by parameterizing the simulated diffuse horizontal irradiance and direct normal irradiance for cloudy
conditions from RRTM runs using sixteen-stream discrete ordinates radiative transfer method. The solar irradiance at the
surface was simulated by combining the cloud irradiance parameterizations with a fast clear-sky model, REST2. To
understand the accuracy and efficiency of the newly developed fast model, we analyzed FARMS runs using cloud optical and
microphysical properties retrieved using GOES data from 2009–2012. The global horizontal irradiance for cloudy conditions
was simulated using FARMS and RRTMG with a two-stream approximation and compared to measurements taken from the
U.S. Department of Energy’s Atmospheric Radiation Measurement Climate Research Facility Southern Great Plains site. Our
results indicate that the accuracy of FARMS is comparable to or better than the two-stream approach; however, FARMS is
approximately 400 times more efficient because it does not explicitly solve the radiative transfer equation for each individual
cloud condition. Radiative transfer model runs are computationally expensive, but this model is promising for broad
applications in solar resource assessment and forecasting. It is currently being used in the National Solar Radiation Data
Base, which is publicly available from the National Renewable Energy Laboratory at http://nsrdb.nrel.gov.
Stability analysis of pressure correction schemes for the Navier-Stokes equations with traction boundary conditions
Creators: name: Lee, Sanghyun
name: Salgado, Abner J.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Numerical Analysis (math.NA)
subject: FOS: Mathematics

description: We present a stability analysis for two different rotational pressure correction schemes with open and traction boundary conditions. First, we provide a stability analysis for a rotational version of the grad-div stabilized scheme of [A. Bonito, J.-L. Guermond, and S. Lee. Modified pressure-correction projection methods: Open boundary and variable time stepping. In Numerical Mathematics and Advanced Applications - ENUMATH 2013, volume 103 of Lecture Notes in Computational Science and Engineering, pages 623-631. Springer, 2015]. This scheme turns out to be unconditionally stable, provided the stabilization parameter is suitably chosen. We also establish a conditional stability result for the boundary correction scheme presented in [E. Bansch. A finite element pressure correction scheme for the Navier-Stokes equations with traction boundary condition. Comput. Methods Appl. Mech. Engrg., 279:198-211, 2014]. These results are shown by employing the equivalence between stabilized gauge Uzawa methods and rotational pressure correction schemes with traction boundary conditions.
Shortest Term Forecasting of DNI for Concentrated Solar Technologies
Creators: name: Müller, S.C.
name: Remund, J.
Publisher: name: WIP
Year: 2016
Subjects: Operation, Performance, Reliability and Sustainability of Photovoltaics
Solar Resource and Forecasting

description: 32nd European Photovoltaic Solar Energy Conference and Exhibition; 1490-1492
description: Accurate knowledge of the future state of direct normal irradiance (DNI) is needed for the successful
operation of concentrated solar technologies like concentrating solar power (CSP) or concentrating photovoltaics
(CPV). For different applications within a power plant forecast horizons of 0 to 4 hours with spatial resolutions from
meters to kilometers are required. The model presented here uses satellite images from MSG satellite as a basis for a
cloud motion nowcasting to derive the DNI. Forecasts are evaluated at four locations in Southern Spain and Northern
Africa for two three monthly time periods in 2010 and 2013. Uncertainties were found for the North African locations
of 120 to 250 W/m2 (22 - 55%) root mean square error and larger deviations in Southern Spain mostly due to
complexity of topography.
The Target-selection Pipeline for the Dark Energy Spectroscopic Instrument
Creators: name: Myers, Adam D.
name: Moustakas, John
name: Bailey, Stephen
name: Weaver, Benjamin A.
name: Cooper, Andrew P.
name: Forero-Romero, Jaime E.
name: Abolfathi, Bela
name: Alexander, David M.
name: Brooks, David
name: Chaussidon, Edmond
name: Chuang, Chia-Hsun
name: Dawson, Kyle
name: Dey, Arjun
name: Dey, Biprateep
name: Dhungana, Govinda
name: Doel, Peter
name: Fanning, Kevin
name: Gaztañaga, Enrique
name: Gontcho, Satya Gontcho A
name: Gonzalez-Morales, Alma X.
name: Hahn, ChangHoon
name: Herrera-Alcantar, Hiram K.
name: Honscheid, Klaus
name: Ishak, Mustapha
name: Karim, Tanveer
name: Kirkby, David
name: Kisner, Theodore
name: Koposov, Sergey E.
name: Kremin, Anthony
name: Lan, Ting-Wen
name: Landriau, Martin
name: Lang, Dustin
name: Levi, Michael E.
name: Magneville, Christophe
name: Napolitano, Lucas
name: Martini, Paul
name: Meisner, Aaron
name: Newman, Jeffrey A.
name: Palanque-Delabrouille, Nathalie
name: Percival, Will
name: Poppett, Claire
name: Prada, Francisco
name: Raichoor, Anand
name: Ross, Ashley J.
name: Schlafly, Edward F.
name: Schlegel, David
name: Schubnell, Michael
name: Tan, Ting
name: Tarle, Gregory
name: Wilson, Michael J.
name: Yèche, Christophe
name: Zhou, Rongpu
name: Zhou, Zhimin
name: Zou, Hu
Publisher: name: arXiv
Year: 2022
Subjects: subject: Instrumentation and Methods for Astrophysics (astro-ph.IM)
subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: In 2021 May, the Dark Energy Spectroscopic Instrument (DESI) began a 5 yr survey of approximately 50 million total extragalactic and Galactic targets. The primary DESI dark-time targets are emission line galaxies (ELGs), luminous red galaxies (LRGs) and quasars (QSOs). In bright time, DESI will focus on two surveys known as the Bright Galaxy Survey (BGS) and the Milky Way Survey (MWS). DESI also observes a selection of "secondary" targets for bespoke science goals. This paper gives an overview of the publicly available pipeline (desitarget) used to process targets for DESI observations. Highlights include details of the different DESI survey targeting phases, the targeting ID (TARGETID) used to define unique targets, the bitmasks used to indicate a particular type of target, the data model and structure of DESI targeting files, and examples of how to access and use the desitarget code base. This paper will also describe "supporting" DESI target classes, such as standard stars, sky locations, and random catalogs that mimic the angular selection function of DESI targets. The DESI target selection pipeline is complex and sizable; this paper attempts to summarize the most salient information required to understand and work with DESI targeting data.
description: AJ, accepted, 27 pages, 4 figures, 10 tables, one of a suite of 8 papers detailing targeting for DESI. Minor textual updates to better match the final, accepted version. Also added two missing co-authors
Safe PV Plants with Panel Level Electronics?
Creators: name: Merz, C.
name: Bettenwort, G.
name: Hopf, M.
name: Knopf, H.
name: Laschinski, J.
Publisher: name: WIP
Year: 2016
Subjects: Operation, Performance, Reliability and Sustainability of Photovoltaics
Balance of System Components

description: 32nd European Photovoltaic Solar Energy Conference and Exhibition; 1499-1501
description: The safety philosophy of PV plants has changed in the last 30 years. With technological progress,
preventive safety measures have been established to increase plant safety as well as personal safety, i.e. double
electrical insulation, residual current monitoring or the arc fault detection. In the last years, requirements for a rapid
shutdown of the PV generator at string level during an emergency came up. In order to comply with the new
requirements, a variety of vendors entered the market with technical solutions. Contrary to intentions, an increase of
serious emergency situations, even fires [3], had to be observed. This shows that the integration of single safety
measures would not increase the plants safety necessarily. The recent requirement for a rapid shutdown on module
level even tightens the situation because it leads to even more components in the PV system using Panel Level
Electronics (PLE). Hence, this paper discusses the harsh operating conditions and system failures that can occur
within a PV plant and which directly affect the design of PLE.
Forecasting and Observability: Critical Technologies for System Operations with High PV Penetration
Creators: name: Alet, P.-J.
name: Efthymiou, V.
name: Graditi, G.
name: Henze, N.
name: Juel, M.
name: Moser, D.
name: Nemac, F.
name: Pierro, M.
name: Rikos, E.
name: Tselepis, S.
name: Yang, G.
Publisher: name: WIP
Year: 2016
Subjects: Operation, Performance, Reliability and Sustainability of Photovoltaics
Solar Resource and Forecasting

description: 32nd European Photovoltaic Solar Energy Conference and Exhibition; 1444-1448
description: Forecasting and monitoring technologies for photovoltaics are required on different spatial and temporal
scales by multiple actors, from the owners of PV systems to transmission system operators. In this paper the Grid
integration working group of the European Technology and Innovation Platform – Photovoltaics (ETIP PV) reviews
the different use cases for these technologies, their current status, and the need for future developments.
Power system operations require a real-time view of PV production for managing power reserves and for feeding shortterm
forecasts. They also require forecasts on all timescales from the short (for dispatching purposes), where statistical
models work best, to the very long (for infrastructure planning), where physics-based models are more accurate. Power
system regulations are driving the development of these techniques. This application also provides a good basis for a
cost/benefit analysis since the forecasting error can be linked to the prices charged for energy imbalance.
Inflationary field excursion in broad classes of scalar field models
Creators: name: Banerjee, Argha
name: Koley, Ratna
Publisher: name: arXiv
Year: 2015
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: In single field slow roll inflation models the height and slope of the potential are to satisfy certain conditions, to match with observations. This in turn translates into bounds on the number of e-foldings and the excursion of the scalar field during inflation. In this work we consider broad classes of inflationary models to study how much the field excursion starting from horizon exit to the end of inflation, $Δϕ$, can vary for the set of inflationary parameters given by Planck. We also derive an upper bound on the number of e-foldings between the horizon exit of a cosmologically interesting mode and the end of inflation. We comment on the possibility of having super-Planckian and sub-Planckian field excursions within the framework of single field slow roll inflation.
description: 10 pages, 4 figures, Matches with version published in PRD
Holographic dark energy from the laws of thermodynamics with Rényi entropy
Creators: name: Manoharan, Manosh T.
name: Shaji, N.
name: Mathew, Titus K.
Publisher: name: arXiv
Year: 2022
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: This article investigates the relationship between the holographic principle and the laws of thermodynamics in explaining the late-time acceleration of the universe. First, we explore the possibilities of generating the standard holographic dark energy (SHDE) from the laws of horizon thermodynamics. Except for entropies that follow an exponent stretched area law, unless we redefine the horizon temperature, we found it challenging to construct a one-to-one correspondence between the dark energies defined by the holographic principle and the laws of thermodynamics. Secondly, in SHDE models, unless we invoke some phenomenological interactions, it is impossible to explain the late-time cosmic acceleration with the Hubble horizon as the IR cutoff. On the other hand, it is possible to induce dark energy as an integration constant using the laws of thermodynamics on the Hubble horizon. These motivated us to explore a feasible way to invoke the holographic principle from the laws of horizon thermodynamics. We show that the additional terms that appear in the modified Friedmann equations on using entropies other than the Bekenstein-Hawking entropy in the first law of thermodynamics can behave like a dynamic holographic dark energy (HDE). We study the features of such an HDE with Rényi entropy as the choice without considering any non-standard interactions. Interestingly, the resulting form of dark energy reduces to the standard cosmological constant when Rényi entropy reduces to the Bekenstein-Hawking entropy. By examining different parameters, we affirm the validity of our approach to dark energy, which respects both holographic principle and thermodynamics.
description: 21 pages, 13 figures (including sub-figures). Published in The European Physical Journal C
Performance Analysis of Ecosole HCPV System
Creators: name: Cancro, C.
name: Graditi, G.
name: Ciniglio, G.
name: Leanza, G.
name: Borriello, A.
name: Ferlito, S.
name: Pascarella, F.
name: Carpanelli, M.
name: Borelli, G.
name: Verdilio, D.
name: De Nardis, D.
name: Gilioli, V.
name: Migali, F.
Publisher: name: WIP
Year: 2016
Subjects: Concentrator and Space Applications
Concentrator and Space Systems

description: 32nd European Photovoltaic Solar Energy Conference and Exhibition; 1385-1389
description: The aim of this work is to report the results of the main characterization activities carried out on the
ECOSOLE HCPV prototypal plant realized by BECAR s.r.l. and installed at ENEA Research Center located at
Portici in the south of Italy. After a detailed description of the system main components, the experimental results
regarding the module characterizations, the tracker accuracy, the system optical acceptance, and the module
temperature survey are detailed.
The second part of the paper is focused on the explanation of the performance analysis carried out on the basis of the
data collected during the first three months of operation. Particular attention has been paid to the performance
comparison of the two sub-arrays of the plant: the first one is realized with module using each one its-own inverter,
and the second one is realized with a classic centralized inverter solution. At the end, a procedure for a detailed losses
analysis is reported and the results obtained for a whole sunny day are explained.
Operator Norm Inequalities between Tensor Unfoldings on the Partition Lattice
Creators: name: Wang, Miaoyan
name: Duc, Khanh Dao
name: Fischer, Jonathan
name: Song, Yun S.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Numerical Analysis (math.NA)
subject: Statistics Theory (math.ST)
subject: FOS: Mathematics
subject: 15A60, 15A69, 06B99, 05A18

description: Interest in higher-order tensors has recently surged in data-intensive fields, with a wide range of applications including image processing, blind source separation, community detection, and feature extraction. A common paradigm in tensor-related algorithms advocates unfolding (or flattening) the tensor into a matrix and applying classical methods developed for matrices. Despite the popularity of such techniques, how the functional properties of a tensor changes upon unfolding is currently not well understood. In contrast to the body of existing work which has focused almost exclusively on matricizations, we here consider all possible unfoldings of an order-$k$ tensor, which are in one-to-one correspondence with the set of partitions of $\{1,\ldots,k\}$. We derive general inequalities between the $l^p$-norms of arbitrary unfoldings defined on the partition lattice. In particular, we demonstrate how the spectral norm ($p=2$) of a tensor is bounded by that of its unfoldings, and obtain an improved upper bound on the ratio of the Frobenius norm to the spectral norm of an arbitrary tensor. For specially-structured tensors satisfying a generalized definition of orthogonal decomposability, we prove that the spectral norm remains invariant under specific subsets of unfolding operations.
description: 17 pages, 1 figure
CPVMatch - Concentrating Photovoltaic Modules Using Advanced Technologies and Cells for Highest Efficiencies
Creators: name: Philipps, S.P.
name: Baudrit, M.
name: Hillerich, K.
name: Moreau, V.
name: Parmesani, R.
name: Román Medina, E.
name: Sala, G.
name: Schineller, B.
name: Timò, G.
name: Bett, A.W.
Publisher: name: WIP
Year: 2016
Subjects: Concentrator and Space Applications
III-V-based Devices for Terrestrial and Space Applications

description: 32nd European Photovoltaic Solar Energy Conference and Exhibition; 1393-1398
description: This paper presents the project Concentrating Photovoltaic modules using advanced technologies and
cells for highest efficiencies (CPVMatch), which has received funding from the European Union’s Horizon 2020
research and innovation program. The aim of CPVMatch is to bring practical performance of HCPV closer to its
theoretical limits with research and development in the field of III-V multi-junction solar cells and CPV modules.
Concerning cells, novel wafer bonded four-junction solar cells made of GaInP/GaAs//GaInAs/Ge are optimized with
the target of reaching 48% efficiency under concentration. Moreover, multi-junction solar cell technologies with
advanced materials - like ternary IV element mixtures (i.e. SiGeSn) and nanostructured anti-reflective coatings - are
investigated. Concerning CPV modules the project focuses on both Fresnel-based and mirror-based technologies with
a target efficiency of 40% under high concentrations beyond 800x. Achromatic Fresnel lenses for improved light
management without secondary optics are investigated. In addition, smart, mirror-based HCPV modules are
developed, which include a new mirror-based design, the integration of DC/DC converters and an intelligent tracking
sensor (PSD sensor) at module level. A profound life-cycle and environmental assessment and the development of
adapted characterization methods of new multi-junction solar cells and HCPV modules complete the work plan of
CPVMatch.
Requirement of Durability Test for Organic Photovoltaic and Dye-Sensitized Solar Cell
Creators: name: Hsu, S.-T.
name: Long, Y.-S.
name: Wu, T.-C.
name: Hsieh, H.-H.
Publisher: name: WIP
Year: 2016
Subjects: Thin Film Solar Cells and Modules
Perovskite, Organic and Hybrid devices

description: 32nd European Photovoltaic Solar Energy Conference and Exhibition; 1357-1359
description: Characterizations of organic photovoltaic (OPV) and dye-sensitized solar cell (DSSC) are important in
order to determine the reliable measurements of cell efficiencies and inspect the product’s defects in early stage. This
paper aims to improve the existing durability tests towards a real operating condition for OPV/DSSC. This work
developed a durability test according to parallel tests such as thermal cycle (TC), damp heat (DH), light soaking (LS)
and combined test (TC50+DH). Each test condition has the stress specification, which differs with IEC 61646
designed for thin-film device. Furthermore, results were applied for SEMI Doc. 5598 [1] to develop an evaluation
principle of OPV/DSSC for PV industries to follow up, and harmonized the test guidelines of current-voltage (SEMI
PV57 [2]) and spectrum response (SEMI PV69 [3]). Guidance on the choice of the suitable test conditions of
durability test in the detailed specification is given. Consequently, this standardized test method for OPV/DSSC can
help industry to get reliable performances of emerging PV, and influence the relevant reliability aspect in a long-term
perspective.
Bounds on boosted dark matter from direct detection: The role of energy-dependent cross sections
Creators: name: Bardhan, Debjyoti
name: Bhowmick, Supritha
name: Ghosh, Diptimoy
name: Guha, Atanu
name: Sachdeva, Divya
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: The recoil threshold of Direct Detection experiments limits the mass range of Dark Matter (DM) particles that can be detected, with most DD experiments being blind to sub-MeV DM particles. However, these light DM particles can be boosted to very high energies via collisions with energetic Cosmic Ray electrons. This allows Dark Matter particles to induce detectable recoil in the target of Direct Detection experiments. We derive constraints on scattering cross section of DM and electron, using XENONnT and Super-Kamiokande data. Vector and scalar mediators are considered, in the heavy and light regimes. We discuss the importance of including energy dependent cross sections (due to specific Lorentz structure of the vertex) in our analysis, and show that the bounds can be significantly different than the results obtained assuming constant energy-independent cross-section, often assumed in the literature for simplicity. Our bounds are also compared with other astrophysical and cosmological constraints.
description: 11 pages, 3 figures; Title modified
Energy-aware Scheduling of Virtualized Base Stations in O-RAN with Online Learning
Creators: name: Kalntis, Michail
name: Iosifidis, George
Publisher: name: arXiv
Year: 2022
Subjects: subject: Networking and Internet Architecture (cs.NI)
subject: Machine Learning (cs.LG)
subject: FOS: Computer and information sciences

description: The design of Open Radio Access Network (O-RAN) compliant systems for configuring the virtualized Base Stations (vBSs) is of paramount importance for network operators. This task is challenging since optimizing the vBS scheduling procedure requires knowledge of parameters, which are erratic and demanding to obtain in advance. In this paper, we propose an online learning algorithm for balancing the performance and energy consumption of a vBS. This algorithm provides performance guarantees under unforeseeable conditions, such as non-stationary traffic and network state, and is oblivious to the vBS operation profile. We study the problem in its most general form and we prove that the proposed technique achieves sub-linear regret (i.e., zero average optimality gap) even in a fast-changing environment. By using real-world data and various trace-driven evaluations, our findings indicate savings of up to 74.3% in the power consumption of a vBS in comparison with state-of-the-art benchmarks.
Bogoliubov approach to superfluid-Bose glass phase transition of a disordered Bose-Hubbard Model in weakly interacting regime
Creators: name: Wang, Botao
name: Jiang, Ying
Publisher: name: arXiv
Year: 2015
Subjects: subject: Quantum Gases (cond-mat.quant-gas)
subject: Statistical Mechanics (cond-mat.stat-mech)
subject: FOS: Physical sciences

description: We investigate the disorder effect on coherent fraction and the quantum phase transition of ultracold dilute Bose gases trapped in disordered optical lattices. Within the framework of Bogoliubov theory, an analytical expression for the particle density is derived and the dependence of coherent fraction on disorder strength as well as on lattice depth is discussed. In weak disorder regime, we find a decreased sensitivity of coherent fraction to disorder with the increase of on-site interaction strength. For strong disorder, the quantum phase boundary between superfluid phase and Bose glass phase in the disordered Bose-Hubbard system in weak interaction regime is discussed qualitatively. The obtained phase diagram is in agreement with the empirical square-root law. The dependence of the corresponding critical value of the disorder strength on optical lattice depth is presented as well, and may serve as a reference object for possible experimental investigation.
description: 7 pages, 6 figures
Indoor Characterization of Wind Influence on CPV Modules through Cell-to-Ambient Thermal Resistance Measurements
Creators: name: Chekalin, A.V.
name: Panchak, A.N.
name: Davidyuk, N.Yu.
name: Rumyantsev, V.D.
name: Sadchikov, N.A.
Publisher: name: WIP
Year: 2016
Subjects: Concentrator and Space Applications
III-V-based Devices for Terrestrial and Space Applications

description: 32nd European Photovoltaic Solar Energy Conference and Exhibition; 1407-1410
description: In the work, an “overall” cell-to-ambient thermal resistance rth is measured indoors in solar
concentrator photovoltaic (CPV) modules under “windless” and simulated “windy” conditions. At measurement
procedure, forward current through the cells causes moderate heating of the tested module, simulating heat transfer
and heat dissipation processes, as it occurring under natural sun illumination. Instantly measured voltage drop value
at current flow is used as an indicator of average temperature of the cells. Using the temperature coefficients,
comparison of the voltage values under “cold” and “hot” module conditions allows estimating increase in temperature
of the cells with respect to ambience. The elaborated method of indoor rth evaluation has been applied at
investigations of solar CPV modules based on silicone-on-glass Fresnel lenses and triple-junction GaInP/GaInAs/Ge
cells.
Q$^2$Chemistry: A quantum computation platform for quantum chemistry
Creators: name: Fan, Yi
name: Liu, Jie
name: Zeng, Xiongzhi
name: Xu, Zhiqian
name: Shang, Honghui
name: Li, Zhenyu
name: Yang, Jinlong
Publisher: name: arXiv
Year: 2022
Subjects: subject: Quantum Physics (quant-ph)
subject: Materials Science (cond-mat.mtrl-sci)
subject: Chemical Physics (physics.chem-ph)
subject: FOS: Physical sciences

description: Quantum computer provides new opportunities for quantum chemistry. In this article, we present a versatile, extensible, and efficient software package, named Q$^2$Chemistry, for developing quantum algorithms and quantum inspired classical algorithms in the field of quantum chemistry. In Q$^2$Chemistry, wave function and Hamiltonian can be conveniently mapped into the qubit space, then quantum circuits can be generated according to a specific quantum algorithm already implemented in the package or newly developed by the users. The generated circuits can be dispatched to either a physical quantum computer, if available, or to the internal virtual quantum computer realized by simulating quantum circuit on classical supercomputers. As demonstrated by our benchmark simulations with up to 72 qubit, Q$^2$Chemistry achieves excellent performance in simulating medium scale quantum circuits. Application of Q$^2$Chemistry to simulate molecules and periodic systems are given with performance analysis.
A Case Study of Developing SEMI Standards for Organic Photovoltaic and Dye-Sensitized Solar Cell in Taiwan
Creators: name: Hsu, S.-T.
name: Long, Y.-S.
name: Wu, T.-C.
name: Hsieh, H.-H.
Publisher: name: WIP
Year: 2016
Subjects: Thin Film Solar Cells and Modules
Perovskite, Organic and Hybrid devices

description: 32nd European Photovoltaic Solar Energy Conference and Exhibition; 1360-1362
description: This paper aims to summary the research of pivot SEMI standards about organic photovoltaic (OPV)
and dye-sensitized solar cell (DSSC), which are developed by SEMI OPV and DSSC task force (TF) in Taiwan
during 2013 to 2016. This work proposes three test methods in detailed specifications for OPV/DSSC product,
including current-voltage (I-V), spectrum response (SR) and durability. I-V measurement (SEMI PV57 [1]) is to
evaluate product’s characteristics without capacity effect for OPV/DSSC. SR evaluation (SEMI PV69 [2]) is to
provide a suitable statistic method after solving the slow response time problem for OPV/DSSC, and proposes a
guideline to correct performance data measured on an isothermal platform under STC. Based on these two released
standards, furthermore, durability test (SEMI Doc. 5598 [3]) for OPV/DSSC can improve the existing aging tests
towards a real operating condition, in order to determine its performance accurately and inspect the product’s defect
or weakness in early stage. Through these standardizations, results can help industry to get reliable performances of
OPV/DSSC, and influence the relevant reliability aspect in a long-term perspective.