cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
The HARPS search for southern extra-solar planets. XXXI. Magnetic activity cycles in solar-type stars: statistics and impact on precise radial velocities
Creators: name: Lovis, C
name: Dumusque, X
name: Santos, NC
name: Bouchy, F
name: Mayor, M
name: Pepe, F
name: Queloz, Didier
name: Ségransan, D
name: Udry, S
Publisher: name: Apollo - University of Cambridge Repository
Year: 2021
Subjects: astro-ph.SR
astro-ph.EP

description: Context. Searching for extrasolar planets through radial velocity measurements relies on the stability of stellar photospheres. Aims. We aim at characterizing the statistical properties of magnetic activity cycles, and studying their impact on spectroscopic measurements such as radial velocities, line bisectors and line shapes. Methods. We use data from the HARPS high-precision planet-search sample comprising 304 FGK stars followed over about 7 years. We obtain high-precision Ca II H&K chromospheric activity measurements and convert them to R'HK indices using an updated calibration taking into account stellar metallicity. We study R'HK variability as a function of time and search for possible correlations with radial velocities and line shape parameters. Results. We classify stars according to the magnitude and timescale of the Ca II H&K variability, and identify activity cycles whenever possible. We find that 39+/-8% of old solar-type stars in the solar neighborhood do not show any activity cycles (or only very weak ones), while 61+/-8% do have one. Non-cycling stars are almost only found among G dwarfs and at mean activity levels log R'HK < -4.95. Magnetic cycle amplitude generally decreases with decreasing activity level. A significant fraction of stars exhibit small variations in radial velocities and line shape parameters that are correlated with activity cycles. The sensitivity of radial velocities to magnetic cycles increases towards hotter stars, while late K dwarfs are almost insensitive. Conclusions. Activity cycles do induce long-period, low-amplitude radial velocity variations, at levels up to ~25 m/s. Caution is therefore mandatory when searching for long-period exoplanets. However, these effects can be corrected to high precision by detrending the radial velocity data using simultaneous measurements of Ca II H&K flux and line shape parameters. (Abridged)
Evolution of spin entanglement and an entanglement witness in multiple-quantum NMR experiments
Creators: name: Fel'dman, E. B.
name: Pyrkov, A. N.
Publisher: name: arXiv
Year: 2008
Subjects: subject: Quantum Physics (quant-ph)
subject: Other Condensed Matter (cond-mat.other)
subject: FOS: Physical sciences

description: We investigate the evolution of entanglement in multiple-quantum (MQ) NMR experiments in crystals with pairs of close nuclear spins-1/2. The initial thermodynamic equilibrium state of the system in a strong external magnetic field evolves under the non-secular part of the dipolar Hamiltonian. As a result, MQ coherences of the zeroth and plus/minus second orders appear. A simple condition for the emergence of entanglement is obtained. We show that the measure of the spin pair entanglement, concurrence, coincides qualitatively with the intensity of MQ coherences of the plus/minus second order and hence the entanglement can be studied with MQ NMR methods. We introduce an Entanglement Witness using MQ NMR coherences of the plus/minus second order.
description: 5 pages, 2 figures
Does the place of residence affect land use preferences? Evidence from a choice experiment in Germany
Creators: name: Sagebiel, Julian
name: Glenk, Klaus
name: Meyerhoff, Jürgen
name: Sagebiel, Julian
name: Glenk, Klaus
name: Meyerhoff, Jürgen
Publisher: name: Unknown
Year: 2020
Subjects: subject: Consumer/Household Economics
subject: Landscape preferences
subject: latent class model
subject: spatial heterogeneity
subject: willing-ness to pay

description: Discrete choice experiments can be used to inform policy makers on people’s preferences for landscapes and cultural ecosystem services. Recent studies have shown that the spatial context influences preferences and related willingness to pay values. In this paper we investigate the effect of the landscape surrounding people’s places of residence on their willingness to pay using data from a discrete choice experiment on local land-use changes and cultural ecosystem services throughout Germany. For analysis, we apply a latent class logit model and include landscape categories as explanatory variables for class membership. We find that the different landscapes people live in are correlated with preferences. Especially people from urban areas and farm- and grassland landscapes have larger willingness to pay values for improvements in cultural ecosystem services than people from forest landscapes and cultural landscapes. The results are important for policy makers as different willingness to pay values in different landscapes imply different welfare effects for land use changes. Taking this information into account can help in reaching more efficient resource allocations.
On the low energy brane/anti-brane dynamics
Creators: name: Lu, J. X.
name: Ning, Bo
name: Zhong, Guan-Nan
Publisher: name: arXiv
Year: 2008
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We study the dynamical behavior of a pair of Dp-brane and anti Dp-brane ($0 \leq p \leq 6$) moving parallel to each other in the region where the brane and anti-brane annihilation will not occur and the low energy description is valid. Given this, we perform a general analysis, in the center of mass frame, of the behavior of the effective potential with respect to the relative brane separation and find that the classical orbits of this system are in general unbound except for $p = 6$ case for which classical bound orbits exist. The non-linearity of the low energy DBI action for D-brane is important for the underlying dynamics. We solve also the explicit orbits for $p = 6$ case.
description: 15 pages, 2 figures; shorten version published in Phys. Lett B
Statistical Approach to the Cosmological-Constant Problem on Brane Worlds
Creators: name: Diakonos, F. K.
name: Saridakis, E. N.
Publisher: name: arXiv
Year: 2007
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: We investigate the physically accepted solutions of general Braneworld scenarios, scanning uniformly the associated parameter space. Without making any further assumptions we find that solutions which give "small" Hubble parameters on the physical brane, and therefore "small" effective cosmological constants on the 4D Universe, are far more probable than those with "large" ones. Eventually, their distribution tends to the $δ$-function in the limit of continuous covering of the parameter space.
description: 6 pages, 6 figures, version published in JCAP
Search for direct photons in p+Pb and p+C collisions at sqrt(sNN) = 17.4 GeV
Creators: name: Baumann, Christoph
Publisher: name: arXiv
Year: 2008
Subjects: subject: Nuclear Experiment (nucl-ex)
subject: FOS: Physical sciences

description: Upper limits on direct photon production were determined as a function of the transverse momentum for 0.7 < pT <= 3.2 GeV/c with the WA98 experiment in p+C and p+Pb collisions at sqrt(sNN) = 17.4 GeV. The results are compared to direct photon measurements in Pb+Pb collisions at sqrt(sNN) = 17.3 GeV by WA98. Implications for a possible thermal direct photon contribution are discussed.
description: 4 pages, 3 figures, to appear in the proceedings of the Quark Matter 2008 conference, Jaipur, India, 4-10 Feb 2008
Modeling many-particle mechanical effects of an interacting Rydberg gas
Creators: name: Amthor, Thomas
name: Reetz-Lamour, Markus
name: Giese, Christian
name: Weidemüller, Matthias
Publisher: name: arXiv
Year: 2007
Subjects: subject: Atomic Physics (physics.atom-ph)
subject: FOS: Physical sciences

description: In a recent work [Phys. Rev. Lett. 98, 023004 (2007)] we have investigated the influence of attractive van der Waals interaction on the pair distribution and Penning ionization dynamics of ultracold Rydberg gases. Here we extend this description to atoms initially prepared in Rydberg states exhibiting repulsive interaction. We present calculations based on a Monte Carlo algorithm to simulate the dynamics of many atoms under the influence of both repulsive and attractive longrange interatomic forces. Redistribution to nearby states induced by black body radiation is taken into account, changing the effective interaction potentials. The model agrees with experimental observations, where the ionization rate is found to increase when the excitation laser is blue-detuned from the atomic resonance.
Generalized Discrete Truncated Wigner Approximation for Nonadiabtic Quantum-Classical Dynamics
Creators: name: Lang, Haifeng
name: Vendrell, Oriol
name: Hauke, Philipp
Publisher: name: arXiv
Year: 2021
Subjects: subject: Chemical Physics (physics.chem-ph)
subject: Disordered Systems and Neural Networks (cond-mat.dis-nn)
subject: Quantum Gases (cond-mat.quant-gas)
subject: Atomic Physics (physics.atom-ph)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: Nonadiabatic molecular dynamics occur in a wide range of chemical reactions and femtochemistry experiments involving electronically excited states. These dynamics are hard to treat numerically as the system's complexity increases and it is thus desirable to have accurate yet affordable methods for their simulation. Here, we introduce a linearized semiclassical method, the generalized discrete truncated Wigner approximation (GDTWA), which is well-established in the context of quantum spin lattice systems, into the arena of chemical nonadiabatic systems. In contrast to traditional continuous mapping approaches, e.g. the Meyer-Miller-Stock-Thoss and the spin mappings, GDTWA samples the electron degrees of freedom in a discrete phase space, and thus forbids an unphysical unbounded growth of electronic state populations. The discrete sampling also accounts for an effective reduced but non-vanishing zero-point energy without an explicit parameter, which makes it possible to treat the identity operator and other operators on an equal footing. As numerical benchmarks on two Linear Vibronic Coupling models show, GDTWA has a satisfactory accuracy in a wide parameter regime, independently of whether the dynamics is dominated by relaxation or by coherent interactions. Our results suggest that the method can be very adequate to treat challenging nonadiabatic dynamics problems in chemistry and related fields.
description: 12 pages, 7 figures
Noether theorem for mu-symmetries
Creators: name: Cicogna, G.
name: Gaeta, G.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Mathematical Physics (math-ph)
subject: FOS: Physical sciences
subject: 22E70

description: We give a version of Noether theorem adapted to the framework of mu-symmetries; this extends to such case recent work by Muriel, Romero and Olver in the framework of lambda-symmetries, and connects mu-symmetries of a Lagrangian to a suitably modified conservation law. In some cases this "mu-conservation law'' actually reduces to a standard one; we also note a relation between mu-symmetries and conditional invariants. We also consider the case where the variational principle is itself formulated as requiring vanishing variation under mu-prolonged variation fields, leading to modified Euler-Lagrange equations. In this setting mu-symmetries of the Lagrangian correspond to standard conservation laws as in the standard Noether theorem. We finally propose some applications and examples.
description: 28 pages, to appear in J. Phys. A
The use of latent variable models in policy: A road fraught with peril?
Creators: name: Campbell, Danny
name: Sandorf, Erlend Dancke
name: Campbell, Danny
name: Sandorf, Erlend Dancke
Publisher: name: Unknown
Year: 2020
Subjects: subject: Consumer/Household Economics
subject: Stated preferences
subject: choice modelling
subject: integrated choice and latent variables
subject: hybrid choice model

description: This paper explores the potential usefulness and possible pitfalls of using integrated choice and latent variable models (hybrid choice models) on stated choice data to inform policy. Using a series of Monte-Carlo simulations, we consider how model selection depends on the strength of relationship between the latent variable and preferences and the strength of relationship between the latent variable and the indicator. Our findings show that integrated choice and latent variable models are difficult to estimate, even when the data generating process is known. Ultimately, we show that their use should be driven by the analyst’s belief about the strength of correlations between preferences, the latent variable and indicator. We discuss the implications of our results for policy.
SmartBreakfast project: New Food Products for Innovative Home Appliances
Creators: name: Talens, Clara
name: Santa Cruz, Elena
name: Rios, Yolanda
Publisher: name: Zenodo
Year: 2021
Subjects: online community
conusmer behaviour
smart cooking devices
food innovation
3D food printing

description: Data files for the SmartBreakfast project: New Food Products for Innovative Home Appliances Data file 1: Moderator guide for the SmartBreakfast online
 community
 Data file 2: SmartBreakfast project – EIT Food: partners, objectives and results Data file 3: 3D printer Breakfast Bar Data file 4: Senior consumer test of a 3D printed breakfast bar
description: This project has received funding from the European Institute of Innovation and Technology (EIT) Food (18075) These documents contain extended data to the article submitted to Open Research Europe: Leveraging capabilities for the creation of a smart, healthy and personalized breakfast: a case study of innovation ecosystems in the EU
Territorial use-rights in fishing (TURFs) and the management of small-scale fisheries : the case of Lake Titicaca (Peru)
Creators: name: Levieil, Dominique P.
Publisher: name: University of British Columbia
Year: 2010

description: The purpose of this thesis is to evaluate whether the Territorial Use-Rights in Fishing (TURFs) of Lake Titieaca, Peru, are effective in overcoming the common property problem of typical fisheries and therefore whether TURFs may prove valuable as part of a more formal management system. It has recently been argued that TURFs should be incorporated into small-scale fisheries management schemes since they should be effective in controlling fishing effort, in promoting a more equitable distribution of the benefits from fishing and in reducing administrative inefficiencies. To determine whether TURFs are in fact effective in controlling fishing effort, I examine Lake Titieaca fisheries in Peru. First, I demonstrate the widespread existence of Lake Titicaca's TURFs and their control over the entire shoreline, most of the littoral area and even part of the pelagic area. Second, I document how, in spite of TURFs' illegality, Lake Titieaca shore dwellers are able to combine legal and illegal means to enforce their traditional rights over their fishing areas. Third, by showing that the relative difference between the returns to labour from fishing with those from alternative activities ranges from 50 to more than 100%, I demonstrate that local fishermen capture substantial fishing rents. If one takes into account that most fishing activities are carried out when there is little else to do, this range increases to 90-180%. I thus conclude that Lake Titieaca fisheries have not reached their bioeconomic equilibrium yet and that the predictions of the common property theory do not apply to them. And fourth, I demonstrate that the origins of these rents can be traced to fishermen's membership in TURF-holding communities, their ability to restrict physical access to the shoreline, and the obligations associated with this membership. Among these obligations are the participation in communal projects and celebrations, the fulfillment of administrative or ceremonial responsibilities, and the undertaking of agricultural activities, all of which constrain the amount of household labour available for fishing. In the concluding section, I consider the potential role of TURFs in a formal management context. I show that, in the long term, even formally recognized TURFs would not be sufficient in themselves to prevent overfishing. I therefore propose that Lake Titieaca TURFs be incorporated into a broader, decentralized management strategy which would capitalize on their strengths and promote cooperation between members of shore communities, fisheries scientists and administrators.
Jet Propagation and Mach Cones in (3+1)d Ideal Hydrodynamics
Creators: name: Betz, Barbara
name: Gyulassy, Miklos
name: Rischke, Dirk H.
name: Stöcker, Horst
name: Torrieri, Giorgio
Publisher: name: arXiv
Year: 2008
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: The observation of jet quenching and associated away--side Mach cone--like correlations at RHIC provide powerful ``external'' probes of the sQGP produced in A+A reactions, but it simultaneously raises the question where the jet energy was deposited. The nearly perfect bulk fluidity observed via elliptic flow suggests that Mach cone--like correlations may also be due to rapid local equilibration in the wake of penetrating jets. Multi-particle correlations lend further support to this possibility. However, a combined study of energy deposition and fluid response is needed. We solve numerically 3--dimensional ideal hydrodynamical equations to compute the flow correlation patterns resulting from a variety of possible energy-momentum deposition models. Mach--cone correlations are shown to depend critically on the energy and momentum deposition mechanisms. They only survive for a special limited class of energy--momentum loss models, which assume significantly less longitudinal momentum loss than energy loss per unit length. We conclude that the correct interpretation of away--side jet correlations will require improved understanding and independent experimental constraints on the jet energy--momentum loss to fluid couplings.
description: 4 pages, 3 figures, To appear in the proceedings of Quark Matter 2008
Latest Improvements in Industrial Selective Emitter Technology with Laser Diffusion
Creators: name: Hammer, D.
name: Olkowska-Oetzel, J.
name: Voigt, O.
name: Mäckel, H.
name: Klinke, V.
name: Citro, M.
name: Habenicht, H.
name: Varner, K.
name: Weiss-Wallrath, H.
name: Amiri, S.
name: Nguyen, V.
name: Krümberg, S.
name: Bertsch, S.
name: Winter, P.
name: Keller, S.
name: Fath, P.
Publisher: name: WIP
Year: 2012
Subjects: Wafer-Based Silicon Solar Cells and Materials Technology
Silicon Solar Cell Improvements

description: 27th European Photovoltaic Solar Energy Conference and Exhibition; 1516-1518
description: In this contribution we will present the transfer of the successful C.LAS laser diffusion technology from
Czochralski silicon to multicrystalline silicon. This technology features, in addition to a standard solar cell process, a
local laser diffusion beneath the front contacts after the POCl3 diffusion. This reduces the contact resistance considerably
and thus allows for a higher sheet resistance between the contact fingers. A higher sheet resistance can increase the open
circuit voltage and short circuit current by effectively reducing recombination in the emitter, leading to an efficiency gain
of 0.3 % absolute in production. For multicrystalline silicon several additional physical effects need to be taken into
account for a successful emitter formation process: (i) the surface of acidic etched multicrystalline wafers is less regular
than the alkaline textured surface of Cz wafers leading to a different laser in-coupling and internal heat transfer
influencing the laser emitter formation, (ii) for non-optimized laser parameters metal impurities within the lasered region
can be redistributed and harm the sensitive space charge region and (iii) the quality of multicrystalline silicon varies
spatially and over different wafer suppliers, which requires the process to be robust against these variations. This
presentation will feature a comprehensive theoretical and experimental analysis of these effects and show how our welladjusted
process, consisting of a furnace diffusion combined with a subsequent laser diffusion can effectively deal with
these fundamental issues. This analysis is conducted using state of the art simulation and characterization methods.
Fully Solderable Large-Area Screen-Printed Al-BSF p-Type Mc-Si Solar Cells from 100 % Solar Grade Feedstock Yielding  n > 17 %: Challenges and Potential on Cell and Module Level
Creators: name: Fertig, F.
name: Krauß, K.
name: Geisemeyer, I.
name: Broisch, J.
name: Höffler, H.
name: Odden, J.O.
name: Soiland, A.-K.
name: Rein, S.
Publisher: name: WIP
Year: 2012
Subjects: Wafer-Based Silicon Solar Cells and Materials Technology
Silicon Feedstock, Crystallisation and Wafering

description: 27th European Photovoltaic Solar Energy Conference and Exhibition; 1031-1038
description: A promising alternative to purifying metallurgical grade silicon via the gaseous phase is purification by
for example slag refinement, leaching and solidification yielding so-called solar grade silicon (SoG-Si). Despite
several advantages of SoG-Si, a wider distribution in PV industry has so far been hindered by reservations towards
efficiency potential, reverse bias behaviour, module reliability and material yield. We achieved peak efficiencies over
17 % on standard (15.6×15.6 cm2) industrial fully-solderable screen-printed aluminium back-surface field (SP Al-
BSF) solar cells on multi-crystalline silicon (mc-Si) wafers from 100 % Elkem Solar Silicon (ESSTM). To our
knowledge, this is amongst the highest efficiencies reported for SP Al-BSF cells on 100 % SoG-mc-Si so far. The
average efficiency over an entire brick is 16.6 % which is the same value as for a reference brick from pure polysilicon
feedstock. The reverse bias behaviour of all cells appears to be well suited for standard industrial module
integration concerning global current density and locally resolved power dissipation behaviour.
Coherent switching by detuning a side-coupled quantum-dot system
Creators: name: Valsson, Omar
name: Tang, Chi-Shung
name: Gudmundsson, Vidar
Publisher: name: arXiv
Year: 2008
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: We investigate phase coherent electronic transport in an open quantum system, which consists of quantum dots side-coupled to a nanowire. It is demonstrated that coherent switching can be characterized by adjusting the electronic energy. A comparative analysis of quantum coherence effects in side-coupled quantum-dot systems is presented. Our results demonstrate the relevance of electronic nanodevices based on coherent switching by appropriately detuning the side-coupled quantum dots that are located at variable distance along a wire.
description: 10 RevTeX pages with 14 included png-figures, (pdfLaTeX)
Adsorption and grafting on colloidal interfaces studied by scattering techniques
Creators: name: Oberdisse, Julian
Publisher: name: arXiv
Year: 2007
Subjects: subject: Soft Condensed Matter (cond-mat.soft)
subject: FOS: Physical sciences

description: The adsorption of polymer and surfactant molecules onto colloidal particles or droplets in solution can be characterized non-destructively by scattering techniques. In a first part, the general framework of Dynamic Light Scattering, Small Angle Neutron and X-ray Scattering for the determination of the structure of adsorbed layers, and namely of the density profile, is presented. We then review recent studies of layers of the model polymer poly(ethylene oxide), as homopolymer or part of a block copolymer. In this field, scattering with contrast variation has been shown to be a powerful tool to obtain a detailed description of the layer structure. Adsorption of chemically more complex systems, including polyelectrolytes, polymer complexes, grafted chains and biomacromolecules are also discussed in this review, as well as surfactant adsorption.
Generation Control Centres: Operation and Control on Spanish Electricity System
Creators: name: Llarena, E.
name: Linares, A.
name: Montes, C.
name: González, O.
name: Molina, D.
name: Pío, A.
name: Moncho, J.
name: Friend, M.
name: Rodríguez, J.
name: Cendagorta, M.
Publisher: name: WIP
Year: 2012
Subjects: PV - a Major Electricity Source
PV in the Electricity Mix

description: 27th European Photovoltaic Solar Energy Conference and Exhibition; 4570-4573
description: To guarantee both quality and security of the Spanish electrical supply, Red Eléctrica de España, S.A.
(REE) requires real-time communication with the energy generating facilities, enabling it to know at all times their
conditions and variables of the functioning. This way it can distribute the required instructions about the production
conditions of energy.
For the mentioned agreement between REE and the electricity generators to be safe and efficient, and from the time
of publication of the Royal Decree 1565/2010, it is obligatory for all the renewable sources installations their
integration (or affiliation) to the designated Generation Control Centres.
The aim of this paper is to develop the adaptability of Spanish solar photovoltaic installations to fulfil the technical
requirements of inscription to a Generation Control Centre. The benefits brought by the implementation of this
technology would include taking advantage of this system of continuous and centrally monitoring of every
installation, optimising the resources, reducing operating and maintenance costs and improving the quality of electric
energy delivered to the distribution grid.
Thermal conductivity and phase separation of the crust of accreting neutron stars
Creators: name: Horowitz, C. J.
name: Caballero, O. L.
name: Berry, D. K.
Publisher: name: arXiv
Year: 2008
Subjects: subject: Astrophysics (astro-ph)
subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: Recently, crust cooling times have been measured for neutron stars after extended outbursts. These observations are very sensitive to the thermal conductivity $κ$ of the crust and strongly suggest that $κ$ is large. We perform molecular dynamics simulations of the structure of the crust of an accreting neutron star using a complex composition that includes many impurities. The composition comes from simulations of rapid proton capture nucleosynthesys followed by electron captures. We find that the thermal conductivity is reduced by impurity scattering. In addition, we find phase separation. Some impurities with low atomic number $Z$ are concentrated in a subregion of the simulation volume. For our composition, the solid crust must separate into regions of different compositions. This could lead to an asymmetric star with a quadrupole deformation that radiates gravitational waves. Observations of crust cooling can constrain impurity concentrations.
description: 8 pages, 8 figures, minor changes, PRE in press
Thermodynamics of regular black hole
Creators: name: Myung, Yun Soo
name: Kim, Yong-Wan
name: Park, Young-Jai
Publisher: name: arXiv
Year: 2007
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: We investigate thermodynamics for a magnetically charged regular black hole (MCRBH), which comes from the action of general relativity and nonlinear electromagnetics, comparing with the Reissner-Norström (RN) black hole in both four and two dimensions after dimensional reduction. We find that there is no thermodynamic difference between the regular and RN black holes for a fixed charge $Q$ in both dimensions. This means that the condition for either singularity or regularity at the origin of coordinate does not affect the thermodynamics of black hole. Furthermore, we describe the near-horizon AdS$_2$ thermodynamics of the MCRBH with the connection of the Jackiw-Teitelboim theory. We also identify the near-horizon entropy as the statistical entropy by using the AdS$_2$/CFT$_1$ correspondence.
description: 20 pages, 6 figures, version to appear in GRG
Silane Based CVD Growth, Governing Mechanisms, Material and Concepts
Creators: name: Filtvedt, W.O.
name: Holt, A.
Publisher: name: WIP
Year: 2012
Subjects: Wafer-Based Silicon Solar Cells and Materials Technology
Silicon Feedstock, Crystallisation and Wafering

description: 27th European Photovoltaic Solar Energy Conference and Exhibition; 1039-1041
description: The reactions and mechanisms governing in a monosilane based CVD reactor for polysilicon
production depends on several interrelated factors. The decomposition of the silane molecule undergoes a series of
intermediate stages before forming the final product. The reactant concentration, heat rate, pressure and heat capacity
of the diluent will influence the intermediate reactions and play an important role in the formation of amorphous or
crystalline structures. Others have reported the occurrence of radial dispersed lines throughout silane based fludized
bed beads [1, 2]. The team has been able to reproduce a pattern that appears similar to these patterns in steady state.
The procedure included building and operating a lab reactor for the purpose of depositing silicon on a hot wall. SEM,
Optical microscopy and X-ray diffraction have been used to characterize the depositions.
The Breakdown of Linear Elastic Fracture Mechanics near the Tip of a Rapid Crack
Creators: name: Livne, Ariel
name: Bouchbinder, Eran
name: Fineberg, Jay
Publisher: name: arXiv
Year: 2008
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: We present high resolution measurements of the displacement and strain fields near the tip of a dynamic (Mode I) crack. The experiments are performed on polyacrylamide gels, brittle elastomers whose fracture dynamics mirror those of typical brittle amorphous materials. Over a wide range of propagation velocities ($0.2-0.8c_s$), we compare linear elastic fracture mechanics (LEFM) to the measured near-tip fields. We find that, sufficiently near the tip, the measured stress intensity factor appears to be non-unique, the crack tip significantly deviates from its predicted parabolic form, and the strains ahead of the tip are more singular than the $r^{-1/2}$ divergence predicted by LEFM. These results show how LEFM breaks down as the crack tip is approached.
description: 4 pages, 4 figures, first of a two-paper series (experiments); no change in content, minor textual revisions
A statistical model of COVID-19 testing in populations: effects of sampling bias and testing errors
Creators: name: Böttcher, Lucas
name: D'Orsogna, Maria R.
name: Chou, Tom
Publisher: name: arXiv
Year: 2021
Subjects: subject: Applications (stat.AP)
subject: Physics and Society (physics.soc-ph)
subject: Quantitative Methods (q-bio.QM)
subject: FOS: Computer and information sciences
subject: FOS: Physical sciences
subject: FOS: Biological sciences

description: We develop a statistical model for the testing of disease prevalence in a population. The model assumes a binary test result, positive or negative, but allows for biases in sample selection and both type I (false positive) and type II (false negative) testing errors. Our model also incorporates multiple test types and is able to distinguish between retesting and exclusion after testing. Our quantitative framework allows us to directly interpret testing results as a function of errors and biases. By applying our testing model to COVID-19 testing data and actual case data from specific jurisdictions, we are able to estimate and provide uncertainty quantification of indices that are crucial in a pandemic, such as disease prevalence and fatality ratios.
description: 13 pages, 4 figures, 1 table
Higher order intertwining approach to quasinormal modes
Creators: name: Jana, T.
name: Roy, P.
Publisher: name: arXiv
Year: 2007
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: Using higher order intertwining operators we obtain new exactly solvable potentials admitting quasinormal mode (QNMs) solutions of the Klein-Gordon equation. It is also shown that different potentials exhibiting QNMs can be related through nonlinear supersymmetry.
The Impact of Soldering Materials and Thecell Interconnect Process on CSI Module Reliability
Creators: name: Lifton, A.
name: Murphy, M.
Publisher: name: WIP
Year: 2012
Subjects: Components for PV Systems
PV Modules

description: 27th European Photovoltaic Solar Energy Conference and Exhibition; 3468-3473
description: In the last few years cSi solar cells have been getting thinner and more efficient. This calls for a better
understanding of the materials and processes used to connect these cells in order to optimize current flow and
ultimately the long term reliability of the module itself. The interconnection (soldering) process, a critical step in the
fabrication of the PV module, can affect the stress level within the module. In addition, soldering materials can
influence the overall stress level in a cell and the quality of interconnect.This paper looks at the impact of various
process conditions and materials on module efficiency and reliability. Several key areas were investigated including:
the effect of flux activity and chemistry on interconnect ribbon solderability, the impact of different soldering times
and temperatures on interconnect ribbon peel strength and the effect of copper ribbon quality on the electrical
performance of the interconnects. Several innovative solder alloys and flux chemistries were tested and a variety of
processing and measurement methods were used.
Towards the Technological Pluriverse
Creators: name: Zavala Barreda, Karla
name: Odendaal, Adriaan
Publisher: name: Zenodo
Year: 2021
Subjects: Technological pluriverse, Co-design, algorithms, design practices, board game, digital futures

description: Adriaan Odendaal & Karla Zavala Barreda ask how the design practice of digital technology needs to be fundamentally changed to create a more inclusive digital future. Using the recent board game project Algorithms of Late-Capitalism, they explore new ideas for creating a technological pluriverse in this article. For example, what would happen if we disbanded Silicon Valley start-ups and restructured them into community-based tech collectives? 
Absorption cross section of RN black hole
Creators: name: R., Sini
name: Kuriakose, V. C.
Publisher: name: arXiv
Year: 2007
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: The behavior of a charged scalar field in the RN black hole space time is studied using WKB approximation. In the present work it is assumed that matter waves can get reflected from the event horizon. Using this effect, the Hawking temperature and the absorption cross section for RN black hole placed in a charged scalar field are calculated. The absorption cross section $σ_{abs}$ is found to be inversely proportional to square of the Hawking temperature of the black hole.
description: 6 pages, 2 figures
LRS Bianchi Type I Models with Anisotropic Dark Energy and Constant Deceleration Parameter
Creators: name: Akarsu, Ozgur
name: Kilinc, Can B.
Publisher: name: arXiv
Year: 2008
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: Locally rotationally symmetric (LRS) Bianchi Type I cosmological models are examined in the presence of dynamically anisotropic dark energy and perfect fluid. We assume that the dark energy (DE) is minimally interacting, has dynamical energy density, anisotropic equation of state parameter (EoS). The conservation of the energy-momentum tensor of the DE is assumed to consist of two separately additive conserved parts. A special law is assumed for the deviation from isotropic EoS, which is consistent with the assumption on the conservation of the energy-momentum tensor of the DE. Exact solutions of Einstein's field equations are obtained by assuming a special law of variation for the mean Hubble parameter, which yields a constant value of the deceleration parameter. Geometrical and kinematic properties of the models and the behaviour of the anisotropy of the dark energy has been carried out. The models give dynamically anisotropic expansion history for the universe that allows to fine tune the isotropization of the Bianchi metric, hence the CMB anisotropy.
description: 20 pages, 10 figures. The revised, final version accepted for publication in General Relativity and Gravitation
Additional file 2: of Integrative analysis of DNA methylation and gene expression reveals hepatocellular carcinoma-specific diagnostic biomarkers
Creators: name: Cheng, Jinming
name: Wei, Dongkai
name: Ji, Yuan
name: Chen, Lingli
name: Yang, Liguang
name: Li, Guang
name: Wu, Leilei
name: Hou, Ting
name: Xie, Lu
name: Ding, Guohui
name: Li, Hong
name: Li, Yixue
Publisher: name: figshare
Year: 2018
Subjects: subject: Cell Biology
subject: Genetics
subject: FOS: Biological sciences
subject: Molecular Biology
subject: Biological Sciences not elsewhere classified
subject: Developmental Biology
subject: Marine Biology
subject: Infectious Diseases
subject: FOS: Health sciences
subject: Plant Biology
subject: Virology

description: Figure S1. Promoter methylation of four genes. Figure S2 Stage-related methylation of six HCC-specific CpGs. Figure S3 Gene expression validation of the four genes by qPCR. (PDF 2167Â kb)
Simulation of Distribution Grids with Photovoltaics by Means of Stochastic Load Profiles and Irradiance Data
Creators: name: Bucher, C.
name: Betcke, J.
name: Andersson, G.
name: Bletterie, B.
name: Küng, L.
Publisher: name: WIP
Year: 2012
Subjects: PV Systems
Large PV Power Plants and Distributed PV: System Aspects and Grid Connection

description: 27th European Photovoltaic Solar Energy Conference and Exhibition; 3795-3800
description: A method to perform distribution grid power flow calculations using stochastic load profiles and meteorological data is presented in this paper. The method is based on two previously presented algorithms: The first algorithm generates stochastic household load profiles and the second generates stochastic irradiance data, both using a sampling rate of one minute. Applying this data to an electrical power distribution grid containing a significant number of photovoltaic systems, realistic power flow and system voltage scenarios are obtained. The results are used to precisely answer a broad range of questions concerning grid integration of photovoltaic systems. The main purpose is to find the maximum photovoltaic power which can be installed in a given distribution grid and to evaluate different measures to raise this limit, such as respecting the correlation between irradiance and loads, active power curtailment, reactive power control or power management algorithms.
In contrast to previous works, this paper not only addresses certain situations such as best or worst case scenarios, but
also analyses the entire range of possible outcomes in Monte Carlo style simulations. Unacceptable situations in the power grid (e.g. overvoltages) can be quantified in probability of occurrence, time of day and their durations. The presented method is demonstrated with a five-node radial test feeder and artificial domestic loads with a resolution of one minute, based on a reference load profile from ewz Zurich.
College readiness without borders : a real-world evaluation model for foundation year programs
Creators: name: Calder, Marisa Claire
name: 0000-0003-0449-2818
Publisher: name: The University of Texas at Austin
Year: 2018
Subjects: International education
Higher education
International students
Program assessment
Program evaluation
College readiness
Foundation year programs

description: In recent years, Foundation Year Programs (FYP) for international students have become increasingly popular at U.S. universities. Most pre-college programs for international students consist of pathway programs that offer conditional admission to the university upon completion. At the same time, stand-alone pre-college FYPs where admission to the host university is not guaranteed, particularly for government-sponsored students from the Middle East, are on the rise. However, the growth of these programs has not yet lead to a standardized definition of what holistic college readiness looks like for international students, who have significantly different needs than domestic students in language proficiency, cultural adjustment, and other areas. There is also a significant gap in the literature about how best to evaluate the effectiveness of FYPs given the unique constraints of these programs, particularly the lack of available data on students before and after the FYP. This paper aims to fill this gap by creating a holistic college readiness standard for international students. This standard draws on the Deardorff process model for intercultural competence,1 the Texas College and Career Readiness Standards2 and relevant literature. Additionally, this paper analyzes seven cases of past evaluations of bridge, pathway, and FYPs to develop recommendations for a real-world evaluation model for FYPs where more typical longitudinal or experimental methods of evaluation are unavailable
Rural Africa Electrification Options: Decision Making Support Tool
Creators: name: Pinedo Pascua, I.
name: Huld, T.
name: Szabó, S.
Publisher: name: WIP
Year: 2012
Subjects: PV - a Major Electricity Source
Markets

description: 27th European Photovoltaic Solar Energy Conference and Exhibition; 4627-4630
description: The year 2012 has been designated as the International Year of Sustainable Energy for All by the
United Nations General Assembly. The international community is committed to supporting Africa to address its
energy challenges but the definition of continental priorities and ways of implementation is under national, subregional
and regional African policy domains.
The scope of this work is to present an analytical easy-to-use web-based tool (under development) that can be used to
evaluate the energy capability and economic viability of off-grid technologies in providing electricity services to
remote rural households in Africa.
Indirect Temperature Measurement of CPV Solar Cells Using Wavelength Shift of the Sub-Cells Luminescence Emission Peaks
Creators: name: Menard, E.
name: Meitl, M.
name: Burroughs, S.
Publisher: name: WIP
Year: 2012
Subjects: Material Studies, New Concepts and Ultra-High Efficiency
Terrestrial Concentrator Systems

description: 27th European Photovoltaic Solar Energy Conference and Exhibition; 189-193
description: Modern utility scale concentrator photovoltaic systems rely on the use of high performance multijunction
solar cells to drive down the cost of solar generated electricity. In an effort to drive system
performance up and reduce further manufacturing costs, Semprius is developing a novel class of High
Concentration Photovoltaic (HCPV) modules using transfer printed micro-solar cells.1-4 These
modules are designed to be manufactured using highly scalable manufacturing processes to drive
production costs down and enable the generation of electricity at very competitive levelized cost of
energy (LCOE) in high direct normal incidence areas. These modules currently achieve a word record
conversion efficiency of 33.9% as independently verified by the Spanish Institute of Concentration
Photovoltaic Systems (ISFOC) and the University of Madrid.5 Even though state of the art multijunction
solar cells are nowadays capable of converting over 40% of the incoming Direct Normal
solar Irradiance (DNI) into electricity,6-8 the remaining 60% of the energy is still lost into heat which
needs to be efficiently extracted to prevent over-heating of the solar cells. Accurate measurements of
the operating temperature of the solar cells are necessary in order to optimize a thermal management
solution and to translate the current-voltage (IV) curves of modules measured indoor and on-sun.9
However, performing accurate measurements of the operating temperature of micro-solar cells is
technically challenging. Standard thermocouples or non-contact infra-red techniques are respectively
inappropriate or require the use of high sensitivity IR imagers which can’t be used to measure solar
cells through optics. This paper presents an alternate measurement technique to indirectly measure the
operating temperature of each subcell through the measurement of the wavelength-shift of their
electro- or photo-luminescence emission profile.
Experimental quantum tossing of a single coin
Creators: name: Nguyen, A. T.
name: Frison, J.
name: Huy, K. Phan
name: Massar, S.
Publisher: name: arXiv
Year: 2008
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: The cryptographic protocol of coin tossing consists of two parties, Alice and Bob, that do not trust each other, but want to generate a random bit. If the parties use a classical communication channel and have unlimited computational resources, one of them can always cheat perfectly. Here we analyze in detail how the performance of a quantum coin tossing experiment should be compared to classical protocols, taking into account the inevitable experimental imperfections. We then report an all-optical fiber experiment in which a single coin is tossed whose randomness is higher than achievable by any classical protocol and present some easily realisable cheating strategies by Alice and Bob.
description: 13 pages
Advances in the Understanding of Phosphorus Silicate Glass (PSG) Formation for Accurate Process Simulation of Phosphorus Diffusion
Creators: name: Micard, G.
name: Dastgheib-Shirazi, A.
name: Steyer, M.
name: Wagner, H.
name: Altermatt, P.P.
name: Hahn, G.
Publisher: name: WIP
Year: 2012
Subjects: Wafer-Based Silicon Solar Cells and Materials Technology
Silicon Solar Cell Characterization and Modelling

description: 27th European Photovoltaic Solar Energy Conference and Exhibition; 1355-1359
description: The diffusion of phosphorus mediated by phosphorus oxychloride (POCl3) is extensively used in
photovoltaics due to its enhanced diffusion speed and to the high controllability of the phosphorus at the wafer
surface. However, the POCl3 decomposition in the gas phase in phosphorus pentoxide (P2O5) as well as the
subsequent oxidation reactions induced by P2O5 and O2 at the silicon surface are not very well documented and
increase the complexity of a realistic simulation of the POCl3 diffusion. It is shown in this paper that the PSG growth
model of Ghoshtagore [2] should apply correctly at least in a quantitative relative way to the PSG grown during a
POCl3 diffusion. This model allowed to show that the PSG contains a thin layer of 8.6 nm, presumably composed of
SiO2, which acts as a diffusion barrier with a subsequent impact on the phosphorus diffusion in silicon. In order to
interpret ECV profiles of emitters obtained with various POCl3 flows, a qualitative model based on the Ghoshtagore
model is presented. This model emphasizes the role of O2 at the silicon/PSG interface not only as a mediator of the
PSG growth, but also as a generator of self-interstitials in silicon that will enhance the extension of the ECV profile
tail. It also emphasizes the role of SiP precipitates in reducing the interstitial diffusion in silicon.