cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
""Urban Plant"" Light-Weight Solar System for Parking and other Urban Double Use Applications
Creators: name: Baumgartner, F.P.
name: Büchel, A.
name: Carigiet, F.
name: Baumann, T.
name: Epp, R.
name: Wirtz, A.
name: Hügeli, A.
name: Graf, U.
Publisher: name: WIP
Year: 2013
Subjects: COMPONENTS FOR PV SYSTEMS
Balance of System Components

description: 28th European Photovoltaic Solar Energy Conference and Exhibition; 2897-2901
description: Innovations on all aspects of BOS and solar cell integration into the module are essential to further
reducing the costs of PV electricity and substantial progress has been made in the past years. One other important
aspect is the availability of space for PV power production, especially in densely occupied urban areas. Roof space is
limited or only partially useable. A promising other application for PV power production in urban areas today are PV
carports on parking lots, which require massive structures and foundations. The approach presented here is a newly
developed PV plant which automatically stores the PV modules in a protection box in case of bad weather conditions.
Avoiding bad weather conditions implies that only a fraction of the mechanical load is present on the PV modules
and the structure, enabling light weight structural design. The newly developed PV plant is folding the PV generator
into a protection box and will pull out the PV generator, carried on two supporting cables for operation during good
weather conditions. An innovative autonomous control system was developed based on local meteo sensors and
regional weather information. The PV modules of the Urban Plant are mounted six meters above a parking lot with
the benefit of full double use of the land below. Thus a PV system has been built with currently 52 kW nominal
power, 16 meter wide, with a folding roof of PV modules expanding 24 meters in one direction. The system can be
extended to 104 kWp with a second folding roof expanding into the other direction. As special PV system design was
developed with a light weight PV generator using module laminates with special mounting elements. Moreover the
system comprises innovative string wiring and inverters that can be also integrated into the safety box. A first 250kW
commercial system is scheduled to be set into operation in Jan 2014 in Southern Germany.
Reactive Power Flows of Photovoltaic Inverters with a Power Factor Requirement of One
Creators: name: Spring, A.
name: Wirth, G.
name: Wagler, M.
name: Becker, G.
name: Witzmann, R.
Publisher: name: WIP
Year: 2013
Subjects: COMPONENTS FOR PV SYSTEMS
Balance of System Components

description: 28th European Photovoltaic Solar Energy Conference and Exhibition; 2908-2914
description: The generated power of photovoltaic (PV) systems represents a growing part of the electrical energy supply in
Germany. At the beginning of 2013, more than 32 GW have been installed [BUR-13]. This leads to new challenges to ensure
the required grid stability. Due to the rapid extension of PV systems, primarily in low voltage grids, the state of the grid is
increasingly unknown. This paper discusses reactive power flows due to PV inverter systems. The focus hereby is on the
power factor (PF) requirement of one. Hence PV inverters should feed only active and no reactive power into the grid. Various
observations in low voltage grids show a dispersion of the active and apparent power feed in and thus a reactive power
flow. The direction and extend of these reactive power flows are analysed within this paper.
Comments on Graviton Propagation in Light of GW150914
Creators: name: Ellis, John
name: Mavromatos, Nick E.
name: Nanopoulos, Dimitri V.
Publisher: name: arXiv
Year: 2016
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: The observation of gravitational waves from the Laser Interferometer Gravitational-Wave Observatory (LIGO) event GW150914 may be used to constrain the possibility of Lorentz violation in graviton propagation, and the observation by the Fermi Gamma-Ray Burst Monitor of a transient source in apparent coincidence may be used to constrain the difference between the velocities of light and gravitational waves: $c_g - c_γ< 10^{-17}$.
description: 9 pages, no figures; v2 contains additional description and a Noted Added about constraints from GW151226
Polyolefin Backsheet Protects Solar Modules for a Life Time
Creators: name: Stollwerck, G.
name: Schoeppel, W.
name: Graichen, A.
name: Jaeger, C.
name: Kollesch, M.
Publisher: name: WIP
Year: 2013
Subjects: COMPONENTS FOR PV SYSTEMS
PV Modules

description: 28th European Photovoltaic Solar Energy Conference and Exhibition; 2842-2845
description: The backsheet Scotchshield Film 800, based on cost effective polyolefins shows incredible weathering
stability. Polyolefins are known to withstand harsh environmental conditions. This polyolefin is especially modified
for long term durability. To perform a life time estimate, intensive and long-term weathering tests were performed.
The polyolefin backsheet was tested under harsh temperature and UV conditions in the xenon weatherometer and
QUV-A. In parallel, heat aging was done at temperatures of 110°C to 170°C. An Arrhenius extrapolation of the time
to partial loss of property was done to estimate a service life time. The calculated lifetime of the polyolefin based
backsheet in a standard solar module can be more than 50 years in Germany and Arizona.
Effective photon mass from black-hole formation
Creators: name: Emelyanov, Slava
Publisher: name: arXiv
Year: 2016
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: We compute the value of effective photon mass $m_γ$ at one-loop level in QED in the background of small ($10^{10}\,\text{g} \lesssim M \ll 10^{16}\,\text{g}$) spherically symmetric black hole in asymptotically flat spacetime. This effect is associated with the modification of electron/positron propagator in presence of event horizon. Physical manifestations of black-hole environment are compared with those of hot neutral plasma. We estimate the distance to the nearest black hole from the upper bound on $m_γ$ obtained in the Coulomb-law test. We also find that corrections to electron mass $m_e$ and fine structure constant $α$ at one-loop level in QED are negligible in the weak gravity regime.
description: version to be published in Nuclear Physics B
Preconditioning Effects on CIGS Solar Cells and Modules Based on Metastabilities Caused by the Se-Cu di-Vacancy Complex
Creators: name: Eeles, A.E.
name: Betts, T.R.
name: Gottschalg, R.
Publisher: name: WIP
Year: 2013
Subjects: COMPONENTS FOR PV SYSTEMS
PV Modules

description: 28th European Photovoltaic Solar Energy Conference and Exhibition; 2887-2892
description: The rate of preconditioning and relaxation of 5 different types of CIGS module are investigated.
Two distinct preconditioning effects are observed: one which occurs on a millisecond time scale after
illumination and does not seem to persist and another slower effect brought about by light soaking or forward
voltage bias conditioning. For the slower effect, the rate of performance increase was measured using forward
bias to condition the modules. It was found that the improvement occurred on a logarithmic time scale, i.e.
rapidly at first and then increasingly slowly. The total time for the modules to stabilise varied very widely from a
few seconds to over 7 hours. The rate of relaxation was similarly found to occur on a logarithmic time scale such
that the relaxation of modules in the time it takes them to cool after light soaking cannot be safely ignored. The
implications of this variation in magnitude and rate of the preconditioning for performance measurements is
discussed and a possible measurement scheme for CIGS modules using forward bias instead of light soaking is
proposed.
Factorization and Resummation for Jet Processes
Creators: name: Becher, Thomas
name: Neubert, Matthias
name: Rothen, Lorena
name: Shao, Ding Yu
Publisher: name: arXiv
Year: 2016
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: From a detailed analysis of cone-jet cross sections in effective field theory, we obtain novel factorization theorems which separate the physics associated with different energy scales present in such processes. The relevant low-energy physics is encoded in Wilson lines along the directions of the energetic particles inside the jets. This multi-Wilson-line structure is present even for narrow-cone jets due to the relevance of small-angle soft radiation. We discuss the renormalization-group equations satisfied by these operators. Their solution resums all logarithmically enhanced contributions to such processes, including non-global logarithms. Such logarithms arise in many observables, in particular whenever hard phase-space constraints are imposed, and are not captured with standard resummation techniques. Our formalism provides the basis for higher-order logarithmic resummations of jet and other non-global observables. As a nontrivial consistency check, we use it to obtain explicit two-loop results for all logarithmically enhanced terms in cone-jet cross sections and verify those against numerical fixed-order computations.
description: 59 pages, 15 figures. v2: journal version; v3: corrected sign of (5.11) and a few other typos
Backsheet and Module Durability and Performance and Comparison of Accelerated Testing to Long Term Fielded Modules
Creators: name: Gambogi, W.J.
name: Kopchick, J.G.
name: Felder, T.C.
name: MacMaster, S.W.
name: Bradley, A.
name: Hamzavy, B.
name: Kathmann, E.E.L.
name: Stika, K.M.
name: Trout, T.J.
name: Garreau-Iles, L.G.A.
name: Sample, T.
Publisher: name: WIP
Year: 2013
Subjects: COMPONENTS FOR PV SYSTEMS
PV Modules

description: 28th European Photovoltaic Solar Energy Conference and Exhibition; 2846-2850
description: The composition, properties and construction of a backsheet have a direct bearing on its functional performance in a photovoltaic
module. Typically, the performance properties are examined under fixed stress conditions and the performance and stability of
backsheets to these stress conditions are studied. But exposure to the outdoor environment involves stresses acting sequentially
and simultaneously. The effect of these stresses should be applied to modules as well as components to adequately assess their
impact on performance and durability.
To better understand the expected performance in the field, we have examined established and new backsheet constructions and
characterized their initial properties and durability under the usual accelerated test stressors (heat, humidity, UV, temperature
cycling) and under conditions where these stressors are applied sequentially or simultaneously. We have also investigated
performance of materials under new stress conditions designed to better simulate the operation of a PV module in the outdoor
environment. We have applied weathering conditions based on the expected life of the product under various climates to
temperature and UV exposure using albedo exposure from the back of the module and using transmitted UV light through the
package.
The performance and durability of modules from the field after long outdoor exposure are further examined by non-destructive
and destructive analysis. Backsheet constructions are identified and module performance is assessed using IV, EL, insulation,
color, visual assessment, and ATR-IR spectroscopy. Further assessment employing sampling techniques and a wide range of
analytical methods to better understand chemical and physical changes is also described.
Comparison of Angular Losses of PV Modules Using Various Diffuse Sky Models in Singapore
Creators: name: Khoo, Y. S.
name: Singh, J.P.
name: Walsh, T.M.
name: Aberle, A.G.
Publisher: name: WIP
Year: 2013
Subjects: COMPONENTS FOR PV SYSTEMS
PV Modules

description: 28th European Photovoltaic Solar Energy Conference and Exhibition; 2872-2875
description: Photovoltaic (PV) modules are rated under standard test conditions with normally incident light,
whereas under outdoor conditions photons arrive on a PV module surface at all angles. In this study, the angular
losses of PV modules with planar and textured front glass are investigated for the tropical conditions of Singapore.
Angular reflectance for both modules is first measured using a goniophotometer. From the measurements, the angular
loss factors due to the different radiation components are calculated. Then, the angular losses under Singapore
outdoor conditions are determined using three transposition models: Liu and Jordan, Hay and Davies, and Perez et
alia. The annual angular loss and typical meteorological day angular loss for both module structures are studied. For
all cases studied, the PV module with textured glass has consistently lower angular losses compared to the PV
module with planar glass.
Optical Characteristics of PV Module Front Glasses – Incidence Angle Effects of Various Glass Types and Impact on Annual Energy Yield
Creators: name: Herrmann, W.
name: Rimmelspacher, L.
name: Reuter, M.
Publisher: name: WIP
Year: 2013
Subjects: COMPONENTS FOR PV SYSTEMS
PV Modules

description: 28th European Photovoltaic Solar Energy Conference and Exhibition; 2882-2886
description: In order to optimise the energy output of PV modules commonly front glasses with
antireflective coating or light trapping structures are used. There are various suppliers of front
glasses for PV modules on the market advertising the benefits of their products regarding
optical transmittance and the angular characteristic. However, there is no information
available on a direct comparison of optical properties for various glass types and the
potential impact on annual energy yield for real operating conditions. In fact, gains related to
the improved optical transmittance mean no benefit for the end user as he has to pay for
higher nominal power. Generally, analysis of the optical performance on PV module level is
problematic as optical characteristics of the front glass cannot be absolutely certain
separated from variations in the electrical performance of the PV module. With this
background we performed an experimental study on commercial front glasses from various
European glass manufacturers. Our experimental method allowed a separation of the optical
effects and therefore a benchmarking of the glass types. Results were used to calculate
potential energy yield gains that are related to the angular performance of various front
glasses. For that purpose, solar irradiance data for Cologne were used.
Pt/Ni Counter-Electrodes with Improved Stability for Dye Sensitized Solar Cells
Creators: name: Syrrokostas, G.
name: Leftheriotis, G.
name: Yianoulis, P.
Publisher: name: WIP
Year: 2013
Subjects: THIN FILM SOLAR CELLS
Organic-based PV

description: 28th European Photovoltaic Solar Energy Conference and Exhibition; 2768-2772
description: In this work we investigate the stability of platinum (Pt) electrodes after storage in an electrolyte
solution (0.5M KI, 0.05 M I2 in 90%/10% PC/EG), having the standard synthesis used for dye sensitized solar cells.
The electrodes were prepared by electrodeposition and thermal decomposition of hexachloroplatinic acid (H2PtCl6)
solutions. A decrease of up to 40% in the current density for triiodide reduction was caused by storage in the
electrolyte, except in the case of constant voltage electrodeposition when the deposited Pt charge density was in the
order of 60mC/cm2. The use of electrodeposited Ni electrodes as substrates for Pt deposition was found to prevent the
degradation of the electrodes, even after 50 days of storage in the electrolyte. Nickel has no catalytic effect in the
reduction of triiodide ions and the amount of Ni can be kept to a minimum value, such as below 40mC/cm2, without
significant increment in the preparation cost.
Stacking for machine learning redshifts applied to SDSS galaxies
Creators: name: Zitlau, Roman
name: Hoyle, Ben
name: Paech, Kerstin
name: Weller, Jochen
name: Rau, Markus Michael
name: Seitz, Stella
Publisher: name: arXiv
Year: 2016
Subjects: subject: Instrumentation and Methods for Astrophysics (astro-ph.IM)
subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: Machine Learning (cs.LG)
subject: FOS: Physical sciences
subject: FOS: Computer and information sciences

description: We present an analysis of a general machine learning technique called 'stacking' for the estimation of photometric redshifts. Stacking techniques can feed the photometric redshift estimate, as output by a base algorithm, back into the same algorithm as an additional input feature in a subsequent learning round. We shown how all tested base algorithms benefit from at least one additional stacking round (or layer). To demonstrate the benefit of stacking, we apply the method to both unsupervised machine learning techniques based on self-organising maps (SOMs), and supervised machine learning methods based on decision trees. We explore a range of stacking architectures, such as the number of layers and the number of base learners per layer. Finally we explore the effectiveness of stacking even when using a successful algorithm such as AdaBoost. We observe a significant improvement of between 1.9% and 21% on all computed metrics when stacking is applied to weak learners (such as SOMs and decision trees). When applied to strong learning algorithms (such as AdaBoost) the ratio of improvement shrinks, but still remains positive and is between 0.4% and 2.5% for the explored metrics and comes at almost no additional computational cost.
description: 13 pages, 3 tables, 7 figures version accepted by MNRAS, minor text updates. Results and conclusions unchanged
Parameter Study for Polymer Solar Modules Based on Various Cell Lengths and Light Intensities
Creators: name: Slooff, L.H.
name: Burgers, A.R.
name: Bende, E.E.
name: Veenstra, S.C.
name: Kroon, J.M.
Publisher: name: WIP
Year: 2013
Subjects: THIN FILM SOLAR CELLS
Organic-based PV

description: 28th European Photovoltaic Solar Energy Conference and Exhibition; 2776-2780
description: Polymer solar cells may be applied in portable electronic devices, where light intensity and spectral
distribution of the illuminating source can be very different compared to outdoor applications. As the power output of
solar cells depends on temperature, light intensity and spectrum, the design of the module must be optimized for the
specific illumination conditions in the different applications. The interconnection area between cells in a module must
be as narrow as possible to maximize the active area, also called geometrical fill factor, of the module. Laser scribing
has the potential to realize this. The optimal width of the interconnection zone depends both on technological
limitations, e.g. laser scribe width and the minimal distance between scribes, and electrical limitations like resistive
losses. The latter depends on the generated current in the cell and thus also on illumination intensity. Besides that,
also the type of junction, i.e. a single or tandem junction, will influence the optimal geometry. In this paper a
calculation model is presented that can be used for electrical modeling of polymer cells and modules in order to
optimize the performance for the specific illumination conditions.
title: Cultivating Self-Knowledge in the Writing Classroom: A Study of Contemplative Pedagogy
Creators: name: Featherstone, Jared
Publisher: name: Old Dominion University
publisherIdentifier: https://ror.org/04zjtrb98
publisherIdentifierScheme: ROR
Year: 2024

description: This pedagogical research study examines the effects of Understanding the Self Through Writing and Rhetoric, an undergraduate course designed by the researcher, on students. The course is an example of contemplative writing pedagogy, one that seeks to foreground first-person direct experience of the subject matter and integrates mindfulness meditation and journaling throughout. While writing and rhetoric are common undergraduate subjects to teach, the course focuses on particular, lesser-known aspects of them, internal rhetoric and self-making narrative. A third important part of the course is the examination of how communication technologies, especially social media and messaging applications, affect one’s internal rhetoric and life narratives. The study approach is mainly phenomenological, attempting to understand if and how the course enables students to gain self knowledge. Student writing samples over two semesters were analyzed and coded for emergent themes. Findings suggest that positive intellectual and personal results, including the development of self-knowledge, can be found through examination of student writing assignments.
Equivalent linearization finds nonzero frequency corrections beyond first order
Creators: name: Chattopadhyay, Rohitashwa
name: Chakraborty, Sagar
Publisher: name: arXiv
Year: 2016
Subjects: subject: Chaotic Dynamics (nlin.CD)
subject: Classical Analysis and ODEs (math.CA)
subject: Classical Physics (physics.class-ph)
subject: FOS: Physical sciences
subject: FOS: Mathematics

description: We show that the equivalent linearization technique, when used properly, enables us to calculate frequency corrections of weakly nonlinear oscillators beyond the first order in nonlinearity. We illustrate the method by applying it to the conservative anharmonic oscillators and the nonconservative van der Pol oscillator that are respectively paradigmatic systems for modeling center-type oscillatory states and limit cycle type oscillatory states. The choice of these systems is also prompted by the fact that first order frequency corrections may vanish for both these types of oscillators, thereby rendering the calculation of the higher order corrections rather important. The method presented herein is very general in nature and, hence, in principle applicable to any arbitrary periodic oscillator.
description: 4 pages, Accepted in EPJ B
Solar models in light of new high metallicity measurements from solar wind data
Creators: name: Vagnozzi, Sunny
name: Freese, Katherine
name: Zurbuchen, Thomas H.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: We study the impact of new metallicity measurements, from solar wind data, on the solar model. The "solar modelling problem" refers to the persisting discrepancy between helioseismological observations and predictions of solar models computed implementing state-of-the-art photospheric abundances. We critically reassess the problem, in particular considering the new set of abundances of von Steiger \& Zurbuchen 2016, determined through the \textit{in situ} collection of solar wind samples from polar coronal holes. This new set of abundances indicates a solar metallicity $Z_{\odot} \geq 0.0196 \pm 0.0014$, significantly higher than the currently established value. The new values hint at an abundance of volatile elements (i.e. C, N, O, Ne) close to previous results of Grevesse \& Sauval 1998, whereas the abundance of refractory elements (i.e. Mg, Si, S, Fe) is considerably increased. Using the Linear Solar Model formalism, we determine the variation of helioseismological observables in response to the changes in elemental abundances, in order to explore the consistency of these new measurements with constraints from helioseismology. We find that, for observables that are particularly sensitive to the abundance of volatile elements, in particular the radius of the convective zone boundary (CZB) and the sound speed around the radius of CZB, improved agreement over previous models is obtained. Conversely, the high abundance of refractories correlates with a higher core temperature, resulting in an overproduction of neutrinos and a huge increase in the surface Helium abundance. We conclude that the "solar modelling problem" remains unsolved.
description: 10 pages, 7 figures, accepted for publication in ApJ
A graphical calculus for semi-groupal categories
Creators: name: Hu, Sen
name: Lu, Xuexing
name: Ye, Yu
Publisher: name: arXiv
Year: 2016
Subjects: subject: Combinatorics (math.CO)
subject: Discrete Mathematics (cs.DM)
subject: Mathematical Physics (math-ph)
subject: Category Theory (math.CT)
subject: FOS: Mathematics
subject: FOS: Computer and information sciences
subject: FOS: Physical sciences

description: Around the year 1988, Joyal and Street established a graphical calculus for monoidal categories, which provides a firm foundation for many explorations of graphical notations in mathematics and physics. For a deeper understanding of their work, we consider a similar graphical calculus for semi-groupal categories. We introduce two frameworks to formalize this graphical calculus, a topological one based on the notion of a processive plane graph and a combinatorial one based on the notion of a planarly ordered processive graph, which serves as a combinatorial counterpart of a deformation class of processive plane graphs. We demonstrate the equivalence of Joyal and Street's graphical calculus and the theory of upward planar drawings. We introduce the category of semi-tensor schemes, and give a construction of a free monoidal category on a semi-tensor scheme. We deduce the unit convention as a kind of quotient construction, and show an idea to generalize the unit convention. Finally, we clarify the relation of the unit convention and Joyal and Street's construction of a free monoidal category on a tensor scheme.
description: 32 pages. To appear in Applied Categorical Structures
The GPU-based Parallel Ant Colony System
Creators: name: Skinderowicz, Rafał
Publisher: name: arXiv
Year: 2016
Subjects: subject: Distributed, Parallel, and Cluster Computing (cs.DC)
subject: Artificial Intelligence (cs.AI)
subject: FOS: Computer and information sciences

description: The Ant Colony System (ACS) is, next to Ant Colony Optimization (ACO) and the MAX-MIN Ant System (MMAS), one of the most efficient metaheuristic algorithms inspired by the behavior of ants. In this article we present three novel parallel versions of the ACS for the graphics processing units (GPUs). To the best of our knowledge, this is the first such work on the ACS which shares many key elements of the ACO and the MMAS, but differences in the process of building solutions and updating the pheromone trails make obtaining an efficient parallel version for the GPUs a difficult task. The proposed parallel versions of the ACS differ mainly in their implementations of the pheromone memory. The first two use the standard pheromone matrix, and the third uses a novel selective pheromone memory. Computational experiments conducted on several Travelling Salesman Problem (TSP) instances of sizes ranging from 198 to 2392 cities showed that the parallel ACS on Nvidia Kepler GK104 GPU (1536 CUDA cores) is able to obtain a speedup up to 24.29x vs the sequential ACS running on a single core of Intel Xeon E5-2670 CPU. The parallel ACS with the selective pheromone memory achieved speedups up to 16.85x, but in most cases the obtained solutions were of significantly better quality than for the sequential ACS.
High energy particle collisions and geometry of horizon
Creators: name: Zaslavskii, O. B.
Publisher: name: arXiv
Year: 2016
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We consider collision of two geodesic particles near the horizon of such an axially symmetric black hole (rotating or static) that the metric coefficient $g_{ϕϕ}\rightarrow 0$ there. It is shown that (both for regular and singular horizons) the energy in the centre of mass frame $% E_{c.m.}$ is indefinitely large even without fine-tuning of particles' parameters. Kinematically, this is collision between two rapid particles that approach the horizon almost with the speed of light but at different angles. The latter is the reason why the relative velocity tends to that of light, hence to high $E_{c.m.}$. Our approach is model-independent. It relies on general properties of geometry and is insensitive to the details of material source that supports the geometies of the type under consideration. For several particular models (the stringy black hole, the Brans-Dicke analogue of the Schwarzschild metric and the Janis-Newman-Winicour one) we recover the results found in literature previously.
description: 14 pages. Presentation expanded, typos corrected. To appear in IJMP D
On the vertex Folkman numbers $F_v(a_1, ..., a_s; m - 1)$ when $\max\{a_1, ..., a_s\} = 6$ or $7$
Creators: name: Bikov, Aleksandar
name: Nenov, Nedyalko
Publisher: name: arXiv
Year: 2015
Subjects: subject: Combinatorics (math.CO)
subject: FOS: Mathematics

description: Let $G$ be a graph and $a_1, ..., a_s$ be positive integers. Then $G \overset{v}{\rightarrow} (a_1, ..., a_s)$ means that for every coloring of the vertices of $G$ in $s$ colors there exists $i \in \{1, ..., s\}$, such that there is a monochromatic $a_i$-clique of color $i$. The vertex Folkman number $F_v(a_1, ..., a_s; q)$ is defined by the equality: $$ F_v(a_1, ..., a_s; q) = \min\{|V(G)| : G \overset{v}{\rightarrow} (a_1, ..., a_s) \mbox{ and } K_q \not\subseteq G\}. $$ Let $m = \sum\limits_{i=1}^s (a_i - 1) + 1$. It is easy to see that $F_v(a_1, ..., a_s; q) = m$ if $q \geq m + 1$. In [11] it is proved that $F_v(a_1, ..., a_s; m) = m + \max\{a_1, ..., a_s\}$. We know all the numbers $F_v(a_1, ..., a_s; m - 1)$ when $\max\{a_1, ..., a_s\} \leq 5$ and none of these numbers is known if $\max\{a_1, ..., a_s\} \geq 6$. In this paper we compute the numbers $F_v(a_1, ..., a_s; m - 1)$ when $\max\{a_1, ..., a_s\} = 6$.
description: In the current version we use new faster algorithms with the help of which we reproduce the results from the previous version and we also prove new theorems (Theorem 1.5, Theorem 1.6, Theorem 1.7, Theorem 1.8)
Inverted Polymer Solar Cells Using Sol-Gel Derived Al-Doped Zinc Oxide as Electron Transport Layer
Creators: name: Yu, X.
name: Yu, X.
name: Zhang, J.
name: Hu, Z.
name: Zhao, G.
name: Zhao, Y.
Publisher: name: WIP
Year: 2013
Subjects: THIN FILM SOLAR CELLS
Organic-based PV

description: 28th European Photovoltaic Solar Energy Conference and Exhibition; 2733-2736
description: Inverted polymer solar cells (IPSCs) have been fabricated using sol-gel derived aluminum-doped zinc
oxide (AZO) as the electron transport layer. The morphology and conductivity of AZO films were found to be critical to
the device performance. The experimental results indicated that by adjusting Al-to-Zn ratio of the precursor sol, the
conductivity of AZO film enhanced from 4.68×10-7 to 2.76×10-4 S/cm, the root mean square roughness increased slightly
from 1.31 to 2.13 nm compared with the intrinsic zinc oxide film. The optimized AZO film with 1.0 at.% Al
concentration contributed to extract the electron effectively and improve the contact quality of the interface between AZO
film and active layer, significantly enhanced the device fill factor and further improvement of efficiency by 17%
compared to the device with the intrinsic ZnO. It is demonstrated that the performance of IPSCs could be effectively
improved by controlling Al-doping level.
Carbon Steel Foil as an Electrode Substrate for Solid-State DSC and Hybrid PV Devices
Creators: name: Melgari, P.
name: McGettrick, J.
name: Ketipearchchi, U.
name: Wijdekop, M.
Publisher: name: WIP
Year: 2013
Subjects: THIN FILM SOLAR CELLS
Organic-based PV

description: 28th European Photovoltaic Solar Energy Conference and Exhibition; 2773-2775
description: We report a method to convert a plated carbon steel foil into an anodic electrode substrate for fully
printable Photovoltaic (PV) technologies, such as solid state Dye Solar Cells (sDSC), or Hybrid PV (mesoscopic)
devices. This has been utilised to construct sDSC devices up to 24 cm2 with an efficiency of 1.56% Carbon steel is a
desirable substrate material for the scale-up of PV devices due to its flexibility, light-weight and relative low cost.
Carbon steel is also compatible with high throughput roll-to-roll (R2R) processing. A suitable carbon-steel based
anode for an sDSC device requires: a smooth surface finish to prevent electrical shorting to the cathode; limited
oxidation and associated resistive losses during sintering of the active layer; and a blocking layer to prevent charge
recombination. These requirements have been met by a production grade metal-plated carbon steel substrate that is
subsequently coated with a dense metal oxide blocking layer by spray pyrolysis in air, using bespoke processing
conditions (patent pending).
On the Standard Model predictions for $R_K$ and $R_{K^*}$
Creators: name: Bordone, Marzia
name: Isidori, Gino
name: Pattori, Andrea
Publisher: name: arXiv
Year: 2016
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: High Energy Physics - Experiment (hep-ex)
subject: FOS: Physical sciences

description: We evaluate the impact of radiative corrections in the ratios $Γ[B\to M μ^+μ^-]/Γ[B\to M e^+e^-]$ when the meson $M$ is a $K$ or a $K^*$. Employing the cuts on $m^2_{\ell\ell}$ and the reconstructed $B$-meson mass presently applied by the LHCb Collaboration, such corrections do not exceed a few $\%$. Moreover, their effect is well described (and corrected for) by existing Montecarlo codes. Our analysis reinforces the interest of these observables as clean probe of physics beyond the Standard Model.
description: 6 pages [v3: Added Note on SM predictions for RK* in the low q2 region]
Electrodeposited Flexible Counter Electrodes for Dye-Sensitized Solar Modules
Creators: name: De Rossi, F.
name: Zardetto, V.
name: Di Giacomo, F.
name: Mincuzzi, G.
name: Reale, A.
name: Di Carlo, A.
name: Brown, T.M.
Publisher: name: WIP
Year: 2013
Subjects: THIN FILM SOLAR CELLS
Organic-based PV

description: 28th European Photovoltaic Solar Energy Conference and Exhibition; 2761-2763
description: In this work, we present the application of platinum (Pt) electrodeposition (ED) over a large area
flexible dye-sensitized solar cells (DSCs) counterelectrodes (CEs). The goal was solving the well-known uniformity
problems of Pt deposition over resistive substrates [1], ensuring both high transparency and an effective catalytic
activity, fundamental and contrasting requirements for devices based on metallic photoelectrodes (PEs).
We successfully fabricated a DSC parallel module scaling the ED process up to 8x10cm2 area, by means of a
conducting grid over the substrate. Interestingly, the same grid is also used as sealant in the module architecture. We
also optimised the ED process parameters and obtained a transparent, homogeneous and catalytic Pt layer on ITOPEN
substrates. By assembling this CE on a titanium (Ti) based PE, we obtained a parallel module with a power
conversion efficiency of 2.7% on active area, using commercial available materials. To the best of our knowledge,
this is the first functioning flexible DSC module using an electrodeposited Pt CE on plastic substrate and a TiO2-
based PE on Ti foil.
Quarto-quartic birational maps of $\mathbb{P}_3(\mathbb{C})$
Creators: name: Déserti, Julie
name: Han, Frédéric
Publisher: name: arXiv
Year: 2015
Subjects: subject: Algebraic Geometry (math.AG)
subject: FOS: Mathematics
subject: 14E05, 14E07

description: We construct a determinantal family of quarto-quartic transformations of a complex projective space of dimension $3$ from trigonal curves of degree $8$ and genus $5$. Moreover we show that the variety of $(4,4)$-birational maps of $\mathbb{P}_3(\mathbb{C})$ has at least four irreducible components and describe three of them.
Accelerated Aging Test for Carbon Composite Counter Electrodes Based Dye Sensitized Solar Cells
Creators: name: Hashmi, S.G.
name: Halme, J.
name: Lund, P.
Publisher: name: WIP
Year: 2013
Subjects: THIN FILM SOLAR CELLS
Organic-based PV

description: 28th European Photovoltaic Solar Energy Conference and Exhibition; 2723-2732
description: We report here an accelerated aging test for carbon composite catalyst layer based dye sensitized solar cells (DSSCs) that was performed under artificial light intensity (1000 W/m2) equivalent to 1 Sun and at 60 °C for 1000 hours in the presence of significant fraction of UV light intensity. The performance of the reference DSSCs with thermally platinized counter
electrodes degraded almost completely due to severe electrolyte bleaching, which is an expected result of UV light induced degradation of DSSCs. The performance loss was also accompanied by an increase in the counter electrode charge transfer resistance (RCT). However, DSSCs with
counter electrodes based on carbon composite catalyst layers exhibited markedly more stable photovoltaic performance, showed no visible bleaching of the electrolyte, and their catalytic
activity even improved with a gradual decrement in RCT (from 6 Ωcm2 to 2.6 Ωcm2). The efficiency of the carbon composite based DSSCs was reduced by 35% from the initial efficiency
due to a slight degradation in N719 dye and the corrosion at the silver contacts which caused a small increase in the total cell resistance in both types of DSSCs. The resistance of these carbon composites counter electrode based DSSCs against UV light may potentially reduce the overall manufacturing cost by partially or completely relaxing the need for UV filters in complete DSSC assembly, but this hypothesis as well as the physical and chemical origin for the effect should be
investigated and verified by further studies.
Simulation and Experimental Validation of Superposition Scattering Structures for Efficient Light Trapping in Thin-Film Silicon Solar Cells
Creators: name: Chakanga, K.
name: Siepmann, O.
name: Von Maydell, K.
name: Agert, C.
Publisher: name: WIP
Year: 2013
Subjects: THIN FILM SOLAR CELLS
Silicon-based Thin Film Solar Cells

description: 28th European Photovoltaic Solar Energy Conference and Exhibition; 2684-2688
description: Light trapping is used to increase the optical path of the propagating light and therefore the stabilized
efficiency in thin-film silicon solar cells. Consequently, periodic light in-coupling structures are widely investigated
and experimental studies are used to analyse the potential of new innovative scattering structures. Several scattering
structures with a manifold dimensions have been proposed for optimal light in-coupling in multi-junction solar cells.
In this work, we study the light trapping potential of superposition structures obtained from wet chemically etched
aluminium doped Zink oxide (ZnO:Al) deposited on laser textured glass substrates. Experimentally obtained
dispersion and morphology data are implemented into numerical simulations with Sentaurus TCAD using the finite
difference time domain (FDTDM). The angular distribution intensity (ADI), external quantum efficiency (EQE) and
reflectance are analysed. Subsequently single spot laser texturing is suggested and investigated as a method of
texturing the glass. The ADI of ZnO:Al and reflectance of a-Si:H pin solar cells deposited on the textured films are
analysed experimentally.
Analysis of Excitons Distribution of Bilayer Heterojunction Organic Solar Cell Based on CuPc and C60: Excitons Total Dissociation at the p-n Junction
Creators: name: Dioum, A.
name: Ndao, C.B.
name: Gaye, M.B.
name: Ndiaye, S.
name: Lo, B.
name: Assaid, E.M.
name: Beye, A.C.
Publisher: name: WIP
Year: 2013
Subjects: THIN FILM SOLAR CELLS
Organic-based PV

description: 28th European Photovoltaic Solar Energy Conference and Exhibition; 2697-2703
description: Theoretical insight of the dependence effect of the total excitons dissociation at the p_n junction of a
bilayer-Heterojunction Organic Solar Cell (bHJ-OSC) based on copper phthalocyanine (CuPc) as electron-donor and
fullerene (C60) as electron-acceptor is reported. In order to determine new expression of the optical generation rate and
density of excitons photogenerated in the organic photoactive layer of CuPc/C60 of the bHJ-OSC the T-Matrix theory is
applied with the Abeles mathematical formalism. The excitons density of distribution is investigated introducing new
excitons dissociation parameters at the different interfaces of the organic photoactive region, i.e. the exciton dissociation
velocities Sdp, Sdg, Sdj and Sdn respectively associated to the transparent anode (ITO: Indium thin oxide)/donor (CuPc), the
donor (CuPc)/acceptor (C60) and the acceptor (C60)/metallic cathode (Al: aluminium) interfaces. Moreover, the
competitive role of the monochromatic wavelength  of the incoming light and the thickness w of the organic photoactive
layer (CuPc/C60) on the exciton density is emphasized.
Cosmic shear measurement with maximum likelihood and maximum a posteriori inference
Creators: name: Hall, Alex
name: Taylor, Andy
Publisher: name: arXiv
Year: 2016
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: We investigate the problem of noise bias in maximum likelihood and maximum a posteriori estimators for cosmic shear. We derive the leading and next-to-leading order biases and compute them in the context of galaxy ellipticity measurements, extending previous work on maximum likelihood inference for weak lensing. We show that a large part of the bias on these point estimators can be removed using information already contained in the likelihood when a galaxy model is specified, without the need for external calibration. We test these bias-corrected estimators on simulated galaxy images similar to those expected from planned space-based weak lensing surveys, with promising results. We find that the introduction of an intrinsic shape prior can help with mitigation of noise bias, such that the maximum a posteriori estimate can be made less biased than the maximum likelihood estimate. Second-order terms offer a check on the convergence of the estimators, but are largely sub-dominant. We show how biases propagate to shear estimates, demonstrating in our simple setup that shear biases can be reduced by orders of magnitude and potentially to within the requirements of planned space-based surveys at mild signal-to-noise. We find that second-order terms can exhibit significant cancellations at low signal-to-noise when Gaussian noise is assumed, which has implications for inferring the performance of shear-measurement algorithms from simplified simulations. We discuss the viability of our point estimators as tools for lensing inference, arguing that they allow for the robust measurement of ellipticity and shear.
description: 20 pages, 16 figures. Added more low-S/N simulation results, broad conclusions unchanged. Matches version published in MNRAS
Transient Decay of the Excess Minority of Electrons Density Photogenerated within the Active Layer of a Bulk-Heterojunction Organique Solar Cell
Creators: name: Dioum, A.
name: Ndiaye, S.
name: Gaye, M.B.
name: Lo, B.
name: Assaid, E.M.
name: Beye, A.C.
Publisher: name: WIP
Year: 2013
Subjects: THIN FILM SOLAR CELLS
Organic-based PV

description: 28th European Photovoltaic Solar Energy Conference and Exhibition; 2711-2717
description: Transient decay occurs between two steady states through operating points of a Bulk-Heterojunction
Organic Solar Cell (BHJ-OSC) based on blend of poly (3-hexylthiophene-2, 5-diyl) (P3HT) as electron-donor and a
soluble derivative of fullerene called [6, 6]-phenyl C61-butyric acid methyl ester (PCBM) as electron-acceptor under
various monochromatic wavelength  of irradiation of the spectrum visible is investigated. Basically, since the
phenomenological parameters such as the organic photoactive layer thickness, the electron lifetime, the electron
diffusion length, and the electron mobility are deemed paramount important for the electron generation and collection
at the cathode electrode their dependence effects upon the transient decay of the excess minority of electrons are
reported. Likewise, both the influence of the electrons recombination at the interfaces of the electrodes and the
bimolecular recombination within the bulk of P3HT:PCBM is also especially paid attention.
Critical Temperature Enhancement of Topological Superconductors: A Dynamical Mean Field Study
Creators: name: Nagai, Yuki
name: Hoshino, Shintaro
name: Ota, Yukihiro
Publisher: name: arXiv
Year: 2016
Subjects: subject: Superconductivity (cond-mat.supr-con)
subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: We show that a critical temperature Tc for spin-singlet two-dimensional superconductivity is enhanced by a cooperation between the Zeeman magnetic field and the Rashba spin-orbit coupling, where a superconductivity becomes topologically non-trivial below Tc. The dynamical mean field theory (DMFT) with the segment-based hybridization-expansion continuous-time quantum Monte Carlo impurity solver (ct-HYB) is used for accurately evaluating a critical temperature, without any Fermion sign problem. A strong-coupling approach shows that spin-flip driven local pair hopping leads to part of this enhancement, especially effects of the magnetic field. We propose physical settings suitable for verifying the present calculations, one-atom-layer system on Si(111) and ionic-liquid based electric double-layer transistors (EDLTs).
description: 5 pages, 4 figures, and supplemental materials. Accepted for publication in Physical Review B (Rapid Communications)
Bianalytic Maps Between Free Spectrahedra
Creators: name: Augat, Meric
name: Helton, J. William
name: Klep, Igor
name: McCullough, Scott
Publisher: name: arXiv
Year: 2016
Subjects: subject: Functional Analysis (math.FA)
subject: Complex Variables (math.CV)
subject: FOS: Mathematics
subject: 47L25, 32H02, 52A05 (Primary), 14P10, 32E30, 46L07 (Secondary)

description: Linear matrix inequalities (LMIs) $I_d + \sum_{j=1}^g A_jx_j + \sum_{j=1}^g A_j^*x_j^*\succeq0$ play a role in many areas of applications and the set of solutions to one is called a spectrahedron. LMIs in (dimension--free) matrix variables model most problems in linear systems engineering, and their solution sets D_A are called free spectrahedra. These are exactly the free semialgebraic convex sets. This paper studies free analytic maps between free spectrahedra and, under certain irreducibility assumptions, classifies all those that are bianalytic. The foundation of such maps turns out to be a very small class of birational maps we call convexotonic. The convexotonic maps in g variables sit in correspondence with g-dimensional algebras. If two bounded free spectrahedra D_A and D_B meeting our irreducibility assumptions are free bianalytic with map denoted p, then p must (after possibly an affine linear transform) extend to a convexotonic map corresponding to a g-dimensional algebra spanned by (U-I)A_1,...,(U-I)A_g for some unitary U. Furthermore, B and UA are unitarily equivalent. The article also establishes a Positivstellensatz for free analytic functions whose real part is positive semidefinite on a free spectrahedron and proves a representation for a free analytic map from D_A to D_B (not necessarily bianalytic). Another result shows that a function analytic on any radial expansion of a free spectrahedron is approximable by polynomials uniformly on the spectrahedron. These theorems are needed for classifying free bianalytic maps.
description: v4 (post-production version): 61 pages, fixed Proposition 6.3; includes table of contents. v3 (final version): 58 pages. Reworked introduction