cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
How battery calorimetry can enhance the lifetime and safety of Lithium-ion and post-Li cells
Creators: name: Ziebert, Carlos
name: Uhlmann, Nils
name: Mohsin, Ijaz Ul
name: Rohde, Magnus
name: Seifert, Hans Jürgen
Publisher: name: Karlsruher Institut für Technologie (KIT)
Year: 2020

description: With increasing energy density safety and thermal management of Li-ion batteries is becoming more and more important, because the thermal runaway can cause an ignition or even explosion with simultaneous release of toxic gases. In the last nine years we have established battery calorimetry as a versatile characterization technique, which allows advancements for the thermal management and the safety of batteries. With six adiabatic Accelerating Rate Calorimeters of different sizes and two sensitive Tian-Calvet calorimeters combined with cyclers we operate Europe’s largest battery calorimeter center, which enables the evaluation of thermodynamic, thermal and safety data on material, cell and pack level under quasiadiabatic and isoperibolic environments for both normal and abuse conditions (thermal, electrical, mechanical). Calorimetry allows the collection of quantitative data required for optimum battery performance and safety. This information is applied to define the requirements for thermal management. It will be explained how the two different types of calorimeters can be used for studies on heat generation and dissipation of Li-ion cells. For that purpose, they are coupled to battery cyclers in order to perform the measurements during charging and discharging of the cells under defined thermal conditions, which are quasiadiabatic or isoperibolic. It will be shown that by measuring the specific heat capacity and the heat transfer coefficient the measured temperature data during cycling can be converted into generated and dissipated heat data, which are needed for the adjustment of the thermal management systems. It will be presented how battery calorimeters provide thermodynamic and thermal stability data on materials level, e.g. of anodes, cathodes or electrolytes or there combinations and allow to perform safety tests on cell and pack level by applying thermal, mechanical or electrical abuse conditions. The studies on materials level are especially important for Post-Li cells, which make use of more abundant materials, such as sodium or magnesium instead of Li, nickel and cobalt, because these data help to develop safe cells from the beginning all along the value chain. For the advanced Li-ion technology, a holistic safety assessment is in the focus, because the thermal runaway can have multiple interacting causes and effects. A test in the calorimeter reveals the entire process of the thermal runaway with the different stages of exothermic reactions. As a result of the different tests quantitative and system relevant data for temperature, heat and pressure development of materials and cells are provided. In addition it will be explained how calorimeters allow studying the thermal runaway propagation in order to develop and qualify suitable countermeasures, such as heat protection barriers, which is currently becoming a very hot topic.
The function of connexin43 in neuronal migration and cortical development
Creators: name: Cina, Cima
Publisher: name: University of British Columbia
Year: 2010

description: During brain development, young neurons closely associate with radial glia while migrating from the ventricular zone (VZ) to the cortical plate (CP) of the neocortex. It has previously been shown that gap junctions are needed for this migration to occur properly, but the precise mechanism responsible is unclear. Using reverse transcription-polymerase chain reaction, western blot analysis, and immunohistochemistry, we found that among the family of gap junction proteins, connexin (Cx) 26, Cx36, Cx37, Cx43, and Cx45 were expressed in the mouse neocortex. In addition Cx43 and Cx26 were highly expressed in the radial glia and migrating neurons. Therefore, to examine the role of Cx43 in neuronal migration, we used Cre recombinase, driven by the nestin promoter, to conditionally knock-out a floxed coding DNA of the Cx43 gene in mice. Radial glia in the VZ normally express Cx43. They undergo divisions that produce neurons, and serve as migratory guides for the daughter cells that they produce. Based on histological analysis, we proposed that removing Cx43 from radial glia alters the normal lamination of the mouse neocortex. To monitor newborn neurons, we introduced a plasmid containing green fluorescent protein driven by a neuronal (Tα1 tubulin) promoter into the embryonic neocortex using in utero electroporation. The majority of transfected migrating neurons remained in the VZ/intermediate zone (IZ) of the Cx43 conditional knock-out (Cx43cKO) animals, whereas in Cx43fl/fl mice, neurons migrated through the IZ into the CP, indicating that deletion of Cx43 from nestin-positive cells disrupts neuronal migration. We were able to rescue migration of Cx43cKO neurons by electroporating a cytomegalovirus-Cx43 expression plasmid into the embryonic cortex. In contrast, a C-terminal truncated form of Cx43 failed to rescue migration. In addition, Cx43K²⁵⁸stop/- mice, in which Cx43 lacks the last 125 amino acid residues of the C-terminal tail, gave results similar to those seen with the Cx43cKO mice. Furthermore, we conducted experiments with more specific deletions within the C-terminal tail, and found that a narrow region of 47 amino acid residues is required in directing neuronal migration. This study illustrates that full length Cx43 is required for neuronal migration in the neocortex.
Auto-Sklearn 2.0: Hands-free AutoML via Meta-Learning
Creators: name: Feurer, Matthias
name: Eggensperger, Katharina
name: Falkner, Stefan
name: Lindauer, Marius
name: Hutter, Frank
Publisher: name: Brookline, MA : Microtome Publishing
Year: 2022
Subjects: subject: Automated machine learning
subject: hyperparameter optimization
subject: meta-learning
subject: automated AutoML
subject: benchmark
subject: Dewey Decimal Classification::000 | Allgemeines, Wissenschaft::000 | Informatik, Wissen, Systeme::004 | Informatik

description: Automated Machine Learning (AutoML) supports practitioners and researchers with the tedious task of designing machine learning pipelines and has recently achieved substantial success. In this paper, we introduce new AutoML approaches motivated by our winning submission to the second ChaLearn AutoML challenge. We develop PoSH Auto-sklearn, which enables AutoML systems to work well on large datasets under rigid time limits by using a new, simple and meta-feature-free meta-learning technique and by employing a successful bandit strategy for budget allocation. However, PoSH Auto-sklearn introduces even more ways of running AutoML and might make it harder for users to set it up correctly. Therefore, we also go one step further and study the design space of AutoML itself, proposing a solution towards truly hands-free AutoML. Together, these changes give rise to the next generation of our AutoML system, Auto-sklearn 2.0. We verify the improvements by these additions in an extensive experimental study on 39 AutoML benchmark datasets. We conclude the paper by comparing to other popular AutoML frameworks and Auto-sklearn 1.0, reducing the relative error by up to a factor of 4.5, and yielding a performance in 10 minutes that is substantially better than what Auto-sklearn 1.0 achieves within an hour.
Linking electromagnetic precursors with earthquake dynamics: an approach based on nonextensive fragment and self-affine asperity models
Creators: name: Minadakis, G.
name: Potirakis, S. M.
name: Nomicos, C.
name: Eftaxias, K.
Publisher: name: arXiv
Year: 2011
Subjects: subject: Geophysics (physics.geo-ph)
subject: FOS: Physical sciences

description: EM emissions in a wide frequency spectrum ranging from kHz to MHz are produced by opening cracks, which can be considered as precursors of general fracture. An important feature, observed on both laboratory and geophysical scale, is that the MHz radiation systematically precedes the kHz one. Yet, the link between an individual EM precursor and a distinctive stage of the EQ preparation comprises a crucial open question. A recently proposed two-stage model on preseismic EM activity suggests that the MHz EM emission is due to the fracture of the highly heterogeneous system that surrounds the fault. The finally emerged kHz EM emission is rooted in the final stage of EQ generation, namely, the fracture of entities sustaining the system. In this work we try to further penetrate and elucidate the link of the precursory kHz EM activity with the last stage of EQ generation building on two theoretical models for EQ dynamics. Firstly, the self-affine model states that an EQ is due to the slipping of two rough and rigid fractional Brownian profiles, one over the other, when there is an intersection between them. Secondly, the fragment-asperity model, rooted in a nonextensive Tsallis framework starting from first principles, consists of two rough profiles interacting via fragments filling the gap. In the latter approach, the mechanism of triggering EQ is established through the interaction of the irregularities of the fault planes and the fragments between them. This paper shows that these models of EQ dynamics can be linked with the detected kHz EM emission. In this framework of analysis of preseismic EM activity, we identify sufficient criteria that offer the possibility to discriminate whether a seismic shock is sourced in the fracture of fragments filling the gap between the rough profiles or in the fracture of "teeth" distributed across the fractional Brownian profiles that sustain the system.
The role of extracellular DNA in neutrophil extracellular traps
Creators: name: Halverson, Tyler William Ralph
Publisher: name: Graduate Studies
Year: 2013
Subjects: subject: Sciences
subject: Microbiology
subject: FOS: Biological sciences
subject: Pseudomonas aeurginosa
subject: Neutrophil extracellular traps
subject: extracellular DNA
subject: Neutrophils
subject: Cystic Fibrosis
subject: antimicrobial resistance
subject: surface modifications
subject: defense mechanisms
subject: host-pathogen interactions

description: Pseudomonas aeruginosa is an opportunistic pathogen and the primary pathogen in lung infections in patients with Cystic Fibrosis (CF). Neutrophils are recruited to the site of infection to clear the invading bacteria by phagocytosis and neutrophil extracellular trap (NET) formation. NETs are composed of an extracellular lattice of genomic DNA enmeshed with various antimicrobial components normally found within the neutrophil. NETs trap and kill bacteria; however, the killing attributes of NETs are poorly understood. Here we show that the DNA is an important antimicrobial component of NETs. P. aeruginosa senses and responds to DNA in NETs by inducing genes required to survive NET killing. P. aeruginosa uses various surface modifications for NET resistance and secreted enzymes to degrade and neutralize NETs. These defensive strategies promote survival during neutrophil encounters and illustrate a dynamic example of innate immune evasion by P. aeruginosa.
Multi-mode OAM Convergent Transmission with Co-divergent Angle Tailored by Airy Wavefront
Creators: name: Zhao, Yufei
name: Wang, Ziyang
name: Lu, Yilong
name: Guan, Yong Liang
Publisher: name: arXiv
Year: 2023
Subjects: subject: Information Theory (cs.IT)
subject: Signal Processing (eess.SP)
subject: FOS: Computer and information sciences
subject: FOS: Electrical engineering, electronic engineering, information engineering

description: Wireless backhaul offers a more cost-effective, time-efficient, and reconfigurable solution than wired backhaul to connect the edge-computing cells to the core network. As the amount of transmitted data increases, the low-rank characteristic of Line-of-Sight (LoS) channel severely limits the growth of channel capacity in the point-to-point backhaul transmission scenario. Orbital Angular Momentum (OAM), also known as vortex beam, is considered a potentially effective solution for high-capacity LoS wireless transmission. However, due to the shortcomings of its energy divergence and the specificity of multi-mode divergence angles, OAM beams have been difficult to apply in practical communication systems for a long time. In this work, a novel multi-mode convergent transmission with co-scale reception scheme is proposed. OAM beams of different modes can be transmitted with the same beam divergent angle, while the wavefronts are tailored by the ring-shaped Airy compensation lens during propagation, so that the energy will converge to the same spatial area for receiving. Based on this scheme, not only is the Signal-to-Noise Ratio (SNR) greatly improved, but it is also possible to simultaneously receive and demodulate OAM channels multiplexed with different modes in a limited space area. Through prototype experiments, we demonstrated that 3 kinds of OAM modes are tunable, and different channels can be separated simultaneously with receiving power increasing. The measurement isolations between channels are over 11 dB, which ensures a reliable 16-QAM multiplexing wireless transmission demo system. This work may explore the potential applications of OAM-based multi-mode convergent transmission in LoS wireless communications.
description: Airy beam, line-of-sight channel, orbital angular momentum, OAM multi-mode, wireless communication
Investigation of Different Reference Fluids for Viscosity Prediction of Raw Bitumen and Bitumen Mixture Using Corresponding-States Method
Creators: name: Labbaf, Babak
Publisher: name: Graduate Studies
Year: 2013
Subjects: subject: Chemical
subject: Bitumen viscosity

description: Bitumen consists of different alkane and aromatic compounds and has a greater viscosity than conventional oils. Due to its high viscosity, the mobility of bitumen and, thus, oil should be increased significantly using methods such as solvent-based and thermal recovery oil production processes. Extraction techniques, such as steam-assisted gravity drainage (SAGD) and cyclic steam stimulation (CSS), play an important role in recovering unconventional oil, such as bitumen. A thermal and solvent based method such as expanding solvent steam-assisted gravity drainage (ES-SAGD) technique has been developed to reduce the amount of steam consumed in this process. In all of the aforementioned methods, viscosity plays an important role in the design of the processes. Viscosity is a key transport property in well-designed pipeline and process simulations and also in prediction of production rates. In this research, the focus is on the prediction of viscosity for raw Athabasca bitumen and bitumen mixtures with solvents, such as toluene, xylene and n-decane. In the literature, viscosity corresponding states methods have been used for the prediction of viscosity, with the bitumen characterized into different pseudo-components. Methane has been used as a reference fluid, which is quite inappropriate for bitumen viscosity calculations. This study investigates different reference fluids, such as alkane, cycloalkane and aromatic hydrocarbons. Aromatic hydrocarbons show a closer trend to bitumen viscosity. Higher molecular weight aromatics, such as 1,1 diphenylheptane, can predict Athabasca bitumen viscosity without much deviation. The effects of temperature, pressure and solvent concentration on the prediction of viscosity are examined. The model is tested for the prediction of the viscosity of bitumen mixtures with toluene, xylene and n-decane; and, the resulting absolute deviations from the experimental data are 8.40, 8.05 and 8.54%, respectively. The Lindeloff corresponding states model is also investigated with different reference fluids for the prediction of bitumen viscosity; and, again, 1,1 diphenylheptane results in less deviation from the experimental data than the other studied reference fluids.
Determinants of immediate price impacts at the trade level in an emerging order-driven market
Creators: name: Zhou, Wei-Xing
Publisher: name: arXiv
Year: 2012
Subjects: subject: Statistical Finance (q-fin.ST)
subject: Trading and Market Microstructure (q-fin.TR)
subject: FOS: Economics and business

description: The common wisdom argues that, in general, large trades cause large price changes, while small trades cause small price changes. However, for extremely large price changes, the trade size and news play a minor role, while the liquidity (especially price gaps on the limit order book) is a more influencing factor. Hence, there might be other influencing factors of immediate price impacts of trades. In this paper, through mechanical analysis of price variations before and after a trade of arbitrary size, we identify that the trade size, the bid-ask spread, the price gaps and the outstanding volumes at the bid and ask sides of the limit order book have impacts on the changes of prices. We propose two regression models to investigate the influences of these microscopic factors on the price impact of buyer-initiated partially filled trades, seller-initiated partially filled trades, buyer-initiated filled trades, and seller-initiated filled trades. We find that they have quantitatively similar explanation powers and these factors can account for up to 44% of the price impacts. Large trade sizes, wide bid-ask spreads, high liquidity at the same side and low liquidity at the opposite side will cause a large price impact. We also find that the liquidity at the opposite side has a more influencing impact than the liquidity at the same side. Our results shed new lights on the determinants of immediate price impacts.
description: 21 IOP tex pages including 5 figures and 5 tables. Accepted for publication in New Journal of Physics
Characterisation and Modelling of Continuous-Discontinuous Sheet Moulding Compound Composites for Structural Applications
Creators: name: Trauth, Anna
Publisher: name: KIT Scientific Publishing
Year: 2020
Subjects: Hybride Materialien
Faserverbundwerkstoffe
Modellierung
Charakterisierung
Mechanische Materialeigenschaften
Mikrostruktur
Hybrid materials
fiber composite materials
modelling
characterisation
mechanical material properties
microstructure

description: The main objective of this work is to significantly deepen the understanding of the material and the structural behaviour of continuous-discontinuous SMC composites, following a holistic approach to investigate microscopic aspects, macroscopic mechanical behaviour as well as failure evolution at the coupon, structure and component level. In addition, criteria to evaluate the effect of hybridisation are introduced and modelling approaches are presented and discussed.
Boundary element dynamical energy analysis: a versatile method for solving two or three dimensional wave problems in the high frequency limit
Creators: name: Chappell, David J.
name: Tanner, Gregor
name: Giani, Stefano
Publisher: name: arXiv
Year: 2012
Subjects: subject: Computational Physics (physics.comp-ph)
subject: Numerical Analysis (math.NA)
subject: Chaotic Dynamics (nlin.CD)
subject: FOS: Physical sciences
subject: FOS: Mathematics

description: Dynamical energy analysis was recently introduced as a new method for determining the distribution of mechanical and acoustic wave energy in complex built up structures. The technique interpolates between standard statistical energy analysis and full ray tracing, containing both of these methods as limiting cases. As such the applicability of the method is wide ranging and additionally includes the numerical modelling of problems in optics and more generally of linear wave problems in electromagnetics. In this work we consider a new approach to the method with enhanced versatility, enabling three-dimensional problems to be handled in a straightforward manner. The main challenge is the high dimensionality of the problem: we determine the wave energy density both as a function of the spatial coordinate and momentum (or direction) space. The momentum variables are expressed in separable (polar) coordinates facilitating the use of products of univariate basis expansions. However this is not the case for the spatial argument and so we propose to make use of automated mesh generating routines to both localise the approximation, allowing quadrature costs to be kept moderate, and give versatility in the code for different geometric configurations.
description: arXiv admin note: substantial text overlap with arXiv:1009.3769
Neoliberalism and government responses to Covid-19: Ramifications for early childhood education and care
Creators: name: Sims, Margaret
name: Calder, Pamela
name: Moloney, Mary
name: Rothe, Antje
name: Rogers, Marg
name: Doan, Laura
name: Kakana, Domna
name: Georgiadou, Sofia
Publisher: name: Perth : Curtin University of Technology
Year: 2022
Subjects: subject: Dewey Decimal Classification::300 | Sozialwissenschaften, Soziologie, Anthropologie::370 | Erziehung, Schul- und Bildungswesen

description: The Covid-19 pandemic has created an opportunity to examine the initial policies developed by Australian, Canadian, English, German, Greek and Irish governments to limit the spread of the virus. This has revealed governments’ conceptualisation of the early childhood sector and its workforce. This paper argues that neoliberal ideology and neoliberal imaginaries have already influenced the early childhood sector globally. During the pandemic, the choices that governments made at the outset of the pandemic has allowed their priorities and underlying ideology to be more transparent. Using an ethnographic methodology, early childhood researchers from each of the six countries, examined their individual governments policy responses and the effects on the early childhood sector during its initial months (between March and June 2020). The authors consider the extent to which this may have implications for the sector in how it should continue its ongoing pursuit of professionalisation of the sector. © 2022, Western Australian Institute for Educational Research Inc.. All rights reserved.
A Proof-of-Concept Micro-Pneumatically Controlled Reconfigurable Dielectric Resonator Antenna
Creators: name: Apperley, Thomas
Publisher: name: Engineering
Year: 2013
Subjects: subject: Electronics and Electrical
subject: dielectric resonator antennas
subject: frequency reconfigurable antennas

description: The dielectric resonator antenna (DRA) has several advantages over metallic antennas, which may include low-loss and compact design. However, few frequency reconfiguration methods exist for the DRA. This thesis proposes, designs and validates a new frequency reconfigurable DRA. A proof-of-concept prototype was designed on 101.6 mm x 101.6 mm x 0.508 mm PCB. Frequency reconfigurability was achieved by changing the coupling capacitance between the DRA's fundamental mode and the antenna ground plane by sliding metalized slugs of PCB (3.5 mm x 5.0 mm x 0.29 mm) either under or away from the DRA. The prototype had a measured tuning range of 24.7 % and had two operating frequencies: 21.4 GHz and 16.6 GHz, each with bandwidths of 9.72 % and 6.05 % respectively. The E-plane and H-plane broadside radiation patterns were also measured and were fairly consistent between high and low frequency operation. Keywords: dielectric resonator antennas, frequency reconfigurable antennas
title: Insolvenza civile e concorso
Creators: name: Di Marzio  , Fabrizio
Publisher: name: RomaTrE-Press
Year: 2019

description: Il saggio descrive la struttura del diritto dell’insolvenza nell’ordinamento italiano dove, accanto alle procedure dedicate all’insolvenza delle imprese, ci sono le procedure sul sovraindebitamento. La scarsa considerazione dell’impresa, che costituisce l’elemento distintivo tra il primo e il secondo gruppo, determina un deficit di razionalità e di efficienza del diritto dell’insolvenza considerato nell’insieme. Un recupero di efficienza può essere favorito dall’inserimento della regola per cui la liquidazione giudiziale non determina la cessazione dell’impresa.
description: Obsolescenza e caducità delle leggi civili
Transfer-free fabrication of graphene transistors
Creators: name: Wessely, Pia Juliane
name: Wessely, Frank
name: Birinci, Emrah
name: Riedinger, Bernadette
name: Schwalke, Udo
Publisher: name: arXiv
Year: 2011
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: We invented a method to fabricate graphene transistors on oxidized silicon wafers without the need to transfer graphene layers. To stimulate the growth of graphene layers on oxidized silicon a catalyst system of nanometer thin aluminum/nickel double layer is used. This catalyst system is structured via liftoff before the wafer enters the catalytic chemical vapor deposition (CCVD) chamber. In the subsequent methane based growth process monolayer graphene field-effect transistors (MoLGFETs) and bilayer graphene transistors (BiLGFETs) are realized directly on oxidized silicon substrate, whereby the number of stacked graphene layers is determined by the selected CCVD process parameters, e.g. temperature and gas mixture. Subsequently, Raman spectroscopy is performed within the channel region in between the catalytic areas and the Raman spectra of fivelayer, bilayer and monolayer graphene confirm the existence of graphene grown by this silicon-compatible, transfer-free and in-situ fabrication approach. These graphene FETs will allow a simple and low-cost integration of graphene devices for nanoelectronic applications in a hybrid silicon CMOS environment.
description: 15 pages, 4 figures
Gender inference: can chatGPT outperform common commercial tools?
Creators: name: Alexopoulos, Michelle
name: Lyons, Kelly
name: Mahetaji, Kaushar
name: Barnes, Marcus Emmanuel
name: Gutwillinger, Rogan
Publisher: name: arXiv
Year: 2023
Subjects: subject: Computation and Language (cs.CL)
subject: Artificial Intelligence (cs.AI)
subject: FOS: Computer and information sciences

description: An increasing number of studies use gender information to understand phenomena such as gender bias, inequity in access and participation, or the impact of the Covid pandemic response. Unfortunately, most datasets do not include self-reported gender information, making it necessary for researchers to infer gender from other information, such as names or names and country information. An important limitation of these tools is that they fail to appropriately capture the fact that gender exists on a non-binary scale, however, it remains important to evaluate and compare how well these tools perform in a variety of contexts. In this paper, we compare the performance of a generative Artificial Intelligence (AI) tool ChatGPT with three commercially available list-based and machine learning-based gender inference tools (Namsor, Gender-API, and genderize.io) on a unique dataset. Specifically, we use a large Olympic athlete dataset and report how variations in the input (e.g., first name and first and last name, with and without country information) impact the accuracy of their predictions. We report results for the full set, as well as for the subsets: medal versus non-medal winners, athletes from the largest English-speaking countries, and athletes from East Asia. On these sets, we find that Namsor is the best traditional commercially available tool. However, ChatGPT performs at least as well as Namsor and often outperforms it, especially for the female sample when country and/or last name information is available. All tools perform better on medalists versus non-medalists and on names from English-speaking countries. Although not designed for this purpose, ChatGPT may be a cost-effective tool for gender prediction. In the future, it might even be possible for ChatGPT or other large scale language models to better identify self-reported gender rather than report gender on a binary scale.
description: 14 pages, 8 tables
D3.2: Policy Matrix - Screening of Digital, Data and Water Policies
Creators: name: Knoblauch, Doris
name: Felicetti, Lorenzo
name: Stein, Ulf
name: Bueb, Benedict
name: Kiresiewa, Zoritza
name: Meinecke, Lisa-Fee
name: Caradot, Nicolas
name: Greenhill, Barbara
name: Thirsing, Carsten
name: Bouleau, Gabrielle
name: Dimova, Valentina
name: Kokov, Simeon
Publisher: name: Zenodo
Year: 2020

description: This deliverable introduces the policy matrix for the project digital-water.city. It serves as a framework of reference on the policies impacting smart water management in the five analysed cities (Berlin, Paris, Milan, Copenhagen and Sofia). Policies on water management, data and digitalisation are gathered and evaluated. The Matrix has been the object of a multi-stage peer review on the interplay of local, national and European policies. The final section assesses the status of the legal framework for digital water governance and recommendations for decision-makers on the way forward.
description: Version (v0.1.0) submitted to EC.
Synchronized beamline at FLASH2 based on high-order harmonic generation for two-color dynamics studies
Creators: name: Appi, E.
name: Papadopoulou, C.C.
name: Mapa, J.L.
name: Jusko, C.
name: Mosel, P.
name: Schoenberg, A.
name: Stock, J.
name: Feigl, T.
name: Ališauskas, S.
name: Lang, T.
name: Heyl, C.M.
name: Manschwetus, B.
name: Brachmanski, M.
name: Braune, M.
name: Lindenblatt, H.
name: Trost, F.
name: Meister, S.
name: Schoch, P.
name: Trabattoni, A.
name: Calegari, F.
name: Treusch, R.
name: Moshammer, R.
name: Hartl, I.
name: Morgner, U.
name: Kovacev, M.
Publisher: name: [Erscheinungsort nicht ermittelbar] : American Institute of Physics
Year: 2021
Subjects: subject: Electrons
subject: Harmonic generation
subject: Beam-lines
subject: Color dynamics
subject: Design integrations
subject: Dewey Decimal Classification::500 | Naturwissenschaften::530 | Physik
subject: Dewey Decimal Classification::600 | Technik::620 | Ingenieurwissenschaften und Maschinenbau

description: We present the design, integration, and operation of the novel vacuum ultraviolet (VUV) beamline installed at the free-electron laser (FEL) FLASH. The VUV source is based on high-order harmonic generation (HHG) in gas and is driven by an optical laser system synchronized with the timing structure of the FEL. Ultrashort pulses in the spectral range from 10 to 40 eV are coupled with the FEL in the beamline FL26, which features a reaction microscope (REMI) permanent endstation for time-resolved studies of ultrafast dynamics in atomic and molecular targets. The connection of the high-pressure gas HHG source to the ultra-high vacuum FEL beamline requires a compact and reliable system, able to encounter the challenging vacuum requirements and coupling conditions. First commissioning results show the successful operation of the beamline, reaching a VUV focused beam size of about 20 μm at the REMI endstation. Proof-of-principle photo-electron momentum measurements in argon indicate the source capabilities for future two-color pump-probe experiments.
A Study on the Hydrodynamic Behavior of a Slot-Rectangular Spouted Bed using CFD
Creators: name: Tabatabaei, Seyed Alireza
Publisher: name: Graduate Studies
Year: 2013
Subjects: subject: Chemical
subject: Spouted bed
subject: slot-rectangular
subject: flow regime
subject: Multiphase
subject: two-dimensional
subject: Hydrodynamics
subject: CFD

description: Spouted beds are widely used as gas-solid contactors in various physical and chemical processes. In order to improve the design of spouted beds for efficient gas-solid contact, a better understanding of the complex flow field of granular solids is required. The recognition of flow regimes is also very important in the application of spouted beds. In this thesis, numerical modeling using FLUENT 6.3 commercial software was utilized to study the flow in a slot-rectangular spouted bed. Two-phase gas-solid flows in the bed were simulated with the computational fluid dynamics (CFD) technique using the two-phase Eulerian-Eulerian granular model. Two-dimensional computer simulations were performed to investigate the effects of physical parameters on the hydrodynamic behavior of slot-rectangular spouted beds. The fountain height and pressure drop were evaluated for various superficial gas velocities, bed heights, and solid particle sizes. The numerical results of the fountain height were in good agreement with the experimental data reported elsewhere. The numerical simulations were applied to predict different flow regimes and construct flow regime maps. The constructed flow regime map for a bed containing solid particles with a diameter of 1.44 mm was in good agreement with an experimental map previously reported elsewhere. With this successful numerical mapping, a flow regime map for particles with a diameter of 3.77 mm was constructed for various superficial gas velocities and static bed heights. The map was composed of six distinct flow patterns, i.e., fixed bed, internal jet, jet-in-fluidized-bed, spouting, incoherent spouting, and slugging. The slugging flow regime occurred at large values for the static bed height and air inlet velocity, while the spouting regime arose by increasing the air inlet velocity at low values of static bed height. Unlike the spouting regime, large pressure drop fluctuations were observed in the incoherent spouting regime.
Timing and Code Size Optimization on Achieving Full Parallelism in Uniform Nested Loops
Creators: name: Elloumi, Yaroub
name: Akil, Mohamed
name: Bedoui, Mohamed Hedi
Publisher: name: arXiv
Year: 2012
Subjects: subject: Programming Languages (cs.PL)
subject: FOS: Computer and information sciences
subject: B.2.1; D.4.7
subject: 68M20

description: Multidimensional Retiming is one of the most important optimization techniques to improve timing parameters of nested loops. It consists in exploring the iterative and recursive structures of loops to redistribute computation nodes on cycle periods, and thus to achieve full parallelism. However, this technique introduces a large overhead in a loop generation due to the loop transformation. The provided solutions are generally characterized by an important cycle number and a great code size. It represents the most limiting factors while implementing them in embedded systems. In this paper, we present a new Multidimensional Retiming technique, called "Optimal Multidimensional Retiming" (OMDR). It reveals the timing and data dependency characteristics of nodes, to minimize the overhead. The experimental results show that the average improvement on the execution time of the nested loops by our technique is 19.31% compared to the experiments provided by an existent Multidimensional Retiming Technique. The average code size is reduced by 43.53% compared to previous experiments.
description: 10 pages, 16 figures
Galaxy-scale Star Formation on the Red Sequence: the Continued Growth of S0s and the Quiescence of Ellipticals
Creators: name: Salim, Samir
name: Fang, Jerome J.
name: Rich, R. Michael
name: Faber, S. M.
name: Thilker, David A.
Publisher: name: arXiv
Year: 2012
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: This paper examines star formation (SF) in relatively massive, primarily early-type galaxies (ETGs) at z~0.1. A sample is drawn from bulge-dominated GALEX/SDSS galaxies on the optical red sequence with strong UV excess and yet quiescent SDSS spectra. High-resolution far-UV imaging of 27 such ETGs using HST ACS/SBC reveals structured UV morphology in 93% of the sample, consistent with low-level ongoing SF (~0.5 Ms/yr). In 3/4 of the sample the SF is extended on galaxy scales (25-75 kpc), while the rest contains smaller (5-15 kpc) SF patches in the vicinity of an ETG - presumably gas-rich satellites being disrupted. Optical imaging reveals that all ETGs with galaxy-scale SF in our sample have old stellar disks (mostly S0 type). None is classified as a true elliptical. In our sample, galaxy-scale SF takes the form of UV rings of varying sizes and morphologies. For the majority of such objects we conclude that the gas needed to fuel current SF has been accreted from the IGM, probably in a prolonged, quasi-static manner, leading in some cases to additional disk buildup. The remaining ETGs with galaxy-scale SF have UV and optical morphologies consistent with minor merger-driven SF or with the final stages of SF in fading spirals. Our analysis excludes that all recent SF on the red sequence resulted from gas-rich mergers. We find further evidence that galaxy-scale SF is almost exclusively an S0 phenomenon (~20% S0s have SF) by examining the overall optically red SDSS ETGs. Conclusion is that significant number of field S0s maintain or resume low-level SF because the preventive feedback is not in place or is intermittent. True ellipticals, on the other hand, stay entirely quiescent even in the field.
description: Accepted for publication in ApJ. Contains color figures, but compatible with non-color printers
The Conditions of Consensus: Discipline and Governmentality in Humanitarian Communication
Creators: name: Friesen, Constance
Publisher: name: Graduate Studies
Year: 2013
Subjects: subject: Mass Communications
subject: humanitarian communication
subject: website analysis
subject: Foucault

description: This study engages and builds on the work of those who have examined the prevailing truths that shape humanitarianism and make it appear rational within an inequitable world. Specifically, the study examines how the Canadian Red Cross’s communication practices portray the world’s poorest aid beneficiaries and their potential donors, including their relationship and the world in which they live. The analysis draws on Foucault’s mid-to-late works concerning discipline, governmentality, and biopolitics to examine how truth and subjectivity work together in the context of humanitarian communication. The data are drawn from the Canadian Red Cross (CRC) website, which is the CRC’s primary medium of communication to Canadians. The website’s practices of representation are examined for how they organize a regime of truth and set up the conditions of consensus concerning the relationship between the wealthy and the poor. The study argues that the CRC website’s practices of representation produce aid subjects as problematic, life-threatened bodies that must be trained to become resilient in order to survive a disastrous world. When viewed within an increasingly market-centered global environment, this life-protecting and resiliency-building message can be seen to maintain the consensual conditions in which both the poorest and the wealthy seek not to change the world, but rather only ensure their own survival within it. The message’s cost is that it leads both wealthy and poor away from developing themselves and each other as politically-conscious citizens. The study demonstrates how the construction of subjectivity is a key mechanism in the maintenance of prevailing truths that sustain the wealthy world at the expense of the poor. In addition, the study contributes to the literature by providing a Foucaultian method for analyzing organizational communication texts and websites.
The Universal Severi Variety of Rational Curves on K3 Surfaces
Creators: name: Kemeny, Michael
Publisher: name: arXiv
Year: 2011
Subjects: subject: Algebraic Geometry (math.AG)
subject: FOS: Mathematics

description: We investigate the universal Severi variety of rational curves on K3 surfaces, which parametrises irreducible rational curves in a fixed class on varying K3 surfaces of fixed genus. We investigate the conjecuted irreducibility of this space in the case of primitive classes using the deformation theory of stable maps and obtain partial results. In an appendix we give a short proof of the irreducibility of universal Severi varieties of high genus curves on K3 surfaces.
Noble-Metal Nanorod Cryoaerogels with Electrocatalytically Active Surface Sites
Creators: name: Zámbó, Dániel
name: Rusch, Pascal
name: Lübkemann, Franziska
name: Bigall, Nadja C.
Publisher: name: Washington, DC : Soc.
Year: 2021
Subjects: subject: assembly
subject: cryoaerogel coatings
subject: electrocatalysis
subject: gold nanorods
subject: silver nanorods
subject: Dewey Decimal Classification::500 | Naturwissenschaften::540 | Chemie
subject: Dewey Decimal Classification::600 | Technik

description: Noble-metal-based electrocatalysts usually contain small nanoparticle building blocks to ensure a high specific surface area as the scene for the surface processes. Here, we show that relatively large noble-metal nanorods are also promising candidates to build up functional macrostructures with prominent electrocatalytic activity. After optimizing and upscaling the syntheses of gold nanorods and gold bipyramid-templated silver nanorods, cryoaerogels are fabricated on a conductive substrate via flash freezing and subsequent freeze drying. The versatile cryoaerogelation technique allows the formation of macrostructures with dendritic, open-pore structure facilitating the increase of the accessible nanorod surfaces. It is demonstrated via electrochemical oxidation and stripping test experiments that noble-metal surface sites are electrochemically active in redox reactions. Furthermore, gold nanorod cryoaerogels offer a platform for redox sensing, ethanol oxidation reaction, as well as glucose sensing. Compared to their simply drop-cast and dried counterparts, the noble-metal nanorod cryoaerogels offer enhanced activity due to the open porosity of the fabricated nanostructure while maintaining structural stability.
Temperature-Sensitive Localized Surface Plasmon Resonance of α-NiS Nanoparticles
Creators: name: Himstedt, Rasmus
name: Baabe, Dirk
name: Wesemann, Christoph
name: Bessel, Patrick
name: Hinrichs, Dominik
name: Schlosser, Anja
name: Bigall, Nadja C.
name: Dorfs, Dirk
Publisher: name: Washington, DC : Soc.
Year: 2021
Subjects: subject: Magnetic moments
subject: Magnetic susceptibility
subject: Metal insulator transition
subject: Nanomagnetics
subject: Nickel
subject: Dewey Decimal Classification::500 | Naturwissenschaften::540 | Chemie
subject: Dewey Decimal Classification::500 | Naturwissenschaften::530 | Physik

description: The presented work shows a synthesis route to obtain nanoparticles of the hexagonal α-NiS phase and core-shell particles where the same material is grown onto previously prepared Au seeds. In the bulk, this nickel sulfide phase is known to exhibit a metal-insulator type phase transition (MIT) at 265 K which drastically alters its electrical conductivity. Since the produced nanoparticles show a localized surface plasmon resonance (LSPR) in the visible range of the electromagnetic spectrum, the development of their optical properties depending on the temperature is investigated. This is the first time an LSPR of colloidal nanoparticles is monitored regarding such a transition. The results of UV-vis absorbance measurements show that the LSPR of the particles can be strongly and reversibly tuned by varying the temperature. It can be switched off by cooling the nanoparticles and switched on again by reheating them above the transition temperature. Additional to the phase transition, the temperature-dependent magnetic susceptibility of α-NiS and Au-NiS nanoparticles suggests the presence of different amounts of uncompensated magnetic moments in these compounds that possibly affect the optical properties and may cause the observed quantitative differences in the LSPR response of these materials.
Rectification of Vortex Motion in a Circular Ratchet Channel
Creators: name: Lin, N. S.
name: Heitmann, T. W.
name: Yu, K.
name: Plourde, B. L. T.
name: Misko, V. R.
Publisher: name: arXiv
Year: 2011
Subjects: subject: Superconductivity (cond-mat.supr-con)
subject: FOS: Physical sciences

description: We study the dynamics of vortices in an asymmetric ring channel driven by an external current I in a Corbino setup. The asymmetric potential can rectify the motion of vortices and cause a net flow without any unbiased external drive, which is called ratchet effect. With an applied ac current, the potential can rectify the motion of vortices in the channel and induce a dc net flow. We show that the net flow of vortices strongly depends on vortex density and frequency of the driving current. Depending on the density, we distinguish a "single-vortex" rectification regime (low density) determined by the potential-energy landscape inside each cell of the channel (i.e., "hard" and "easy" directions of motion) and "multi-vortex", or "collective", rectification (high density) when the interaction between vortices becomes important. The frequency of the driving ac current determines a possible distance that a vortex could move during one period. For high frequency current, vortices only oscillate in the triangular cell. For low frequency, the vortex angular velocity $ω$ increases nearly linearly until the driving force reaches the maximum friction force in the hard direction. Furthermore, the commensurability between the number of vortices and the number of cells results in a stepwise $ω-I$ curve. Besides the integer steps, i.e., the large steps found in the single vortex case, we also found fractional steps corresponding to fractional ratio between the numbers of vortices and triangular cells. The principal and fractional frequencies for different currents are found, when the net flow of vortices reaches the maximum that is proportional to the frequency when the density of vortices is low. We have performed preliminary measurements on a device containing a single weak-pinning circular ratchet channel in a Corbino geometry and observed a substantial asymmetric vortex response.
description: 12 pages, 12 figures
Surface moisture increases microcracking and water vapour permeance of apple fruit skin
Creators: name: Khanal, B.P.
name: Imoro, Y.
name: Chen, Y.H.
name: Straube, J.
name: Knoche, M.
Publisher: name: Oxford [u.a.] : Wiley- Blackwell
Year: 2020
Subjects: subject: cuticle
subject: Malus × domestica
subject: microcrack
subject: moisture
subject: transpiration
subject: Dewey Decimal Classification::500 | Naturwissenschaften::580 | Pflanzen (Botanik)

description: Surface moisture induces microcracking in the cuticle of fruit skins. Our objective was to study the effects of surface moisture on cuticular microcracking, the permeance to water vapour and russeting in developing ‘Pinova’ apple fruit. Surface moisture was applied by fixing to the fruit a plastic tube containing deionized water. Microcracking was quantified by fluorescence microscopy and image analysis following infiltration with acridine orange. Water vapour permeance was determined gravimetrically using skin segments (ES) mounted in diffusion cells. Cumulative water loss through the ES increased linearly with time. Throughout development, surface moisture significantly increased skin permeance. The effect was largest during early development and decreased towards maturity. Recovery time courses revealed that following moisture treatment of young fruit for 12 days, skin permeance continued to increase until about 14 days after terminating the moisture treatment. Thereafter, skin permeance decreased over the next 28 days, then approaching the control level. This behaviour indicates gradual healing of the impaired cuticular barrier. Nevertheless, permeance still remained significantly higher compared with the untreated control. Similar patterns of permeance change were observed following moisture treatments at later stages of development. The early moisture treatment beginning at 23 DAFB resulted in russeting of the exposed surfaces. There was no russet in control fruit without a tube or in control fruit with a tube mounted for 12 days without water. The data demonstrate that surface moisture increases microcracking and water vapour permeance. This may lead to the formation of a periderm and, hence, a russeted fruit surface.